2-25-07
The Bride of Christ (contd)
Vigilance & Church Discipline
What is a Church? Part 4
Acts 20:29-31

Summary: Unfaithfulness is the rule, not the exception for most churches. It is a high probability for us. No safeguard will guarantee safety – only vigilance will protect us. Vigilance is frequently commanded, but it is a weakness in the American church. Individually, always be alert – the enemy attacks in your unguarded hours. Corporately, watch for dying ministries and strengthen them. 
The Solution to unfaithfulness is repentance (individual and corporate). Help one another with the 6 steps of church discipline. 
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Introduction
About 2600 years ago there was a place in Asia Minor where there was an impregnable fortress. It was a city that was built on top of cliffs that were over 1000 ft. high. The only way up was through a very narrow passage that could be easily defended. Around the time of the end of Daniel’s life – just before Ezra’s time (about 550 BC) king Croesus ruled all of Lydia, including that city (Sardis).
The convention at that time was for armies to disband during the winter, which is what Croesus did. He disbanded his army for the winter and went to his fortress at Sardis where he was completely safe. But Cyrus (king of Persia) did not disband his army, and he came to Sardis and had his men climb the wall. A child could have defended the city from this kind of attack, but Cyrus got his soldiers up that way and defeated Croesus because Croesus was so over-confident in his fortress that he didn’t have anyone guarding the wall. Three hundred years later the exact same thing happened. They became overconfident, they didn’t guard the walls, and Antiochus the Great had his men climb up the cliffs and sacked the city. (214 BC)
So twice in their history one of the safest cities in the world was defeated because they weren’t on their guard. Then, almost 300 years later, it happened again. Except this time it happened spiritually. Jesus saw that the church in that city had fallen asleep and was not alert – they were not on their guard against unfaithfulness. So Jesus sent a letter to that church about alertness:

Rev.3:2-6  Be alert and strengthen what remains, which is about to die, for I have not found your works complete before My God. 3 Remember therefore what you have received and heard; keep it, and repent. But if you are not alert, I will come like a thief, and you have no idea at what hour I will come against you.

Jesus warned that church that if they did not wake up and become alert Jesus Himself would come against them in judgment in a surprise attack just like what happened with Cyrus and Antiochus. 
We have been studying what the Lord wants from the Church, and today we focus on faithfulness, and unless we want the Lord Jesus Christ to come fight against us in judgment, the warnings we are going to study this morning are very, very important for us to consider and take to heart.
Review
This is our perspective on this study: If there were a group of people who had never heard the word “church” before in their lives – had no idea what it was, and they became Christians and God put them in a room together and told them to function as a church, and the only thing resource they had to find out what that meant was the Bible; what do you think their activities would look like?
Whatever it is - that is our goal in this study. As much as possible we want to set aside any preconceived ideas that are based on tradition and not Scripture and learn from God Himself what He wants His Church to be like. And so we are studying the 5 main metaphors in Scripture for the Church.
The first one was that of a body – the Church is the body of Jesus Christ. And as His body our responsibility is 1) to faithfully represent Him, so when people look at us they get an accurate representation of what Jesus Christ Himself is like; and 2) to reach maturity so we can do His work of filling this world with His grace. And we accomplish that by building up the body by carrying out the one-another commands especially through our spiritual gifts.
The next metaphor is that of a bride. As the bride of Christ we have three wifely duties. The first two we looked at last time: to be beautiful to Him and to be faithful to Him
The thing that is beautiful to Him is our righteousness, purity and holiness. And so we talked about the importance of building one another up, exhorting one another, encouraging one another, and praying for one another when we come together each week. 
Jesus Christ died in order to have a beautiful bride – a purified people eager to do what is good. He paid a high enough price for a beautiful bride; He is worthy to have a beautiful bride, and so we ought to do all we can to make ourselves beautiful to Him.
The second wifely duty we have is faithfulness. Jesus Christ is a Husband who loves us not only with a purifying love, but with a jealous love. He does not want us to commit adultery against Him by letting our hearts be enticed by the world’s concepts of truth. And He is worthy to have a faithful wife. He deserves our exclusive, faithful love, and so we ought do all we can to make sure we do not commit adultery against Him. 
Before we move on to talk about our third wifely duty we need to nail down two important things:
#1 How can we guard ourselves against unfaithfulness to God, and 
#2 What do we do about unfaithfulness and sin when it does happen?
Vigilance
Unfaithfulness is a high probability 
How common do you think it is for a church to go from solid, sound faithfulness to the truth; to compromise, apathy, error and even false doctrine to the point were the entire church needs to repent corporately as a church? I think it is a lot more common than most people realize. 
Jesus sent letters to seven churches in the first Century, and those churches are representative of the way churches have tended to be throughout the Church Age. Notice how Jesus described 5 of those 7 churches:

- you have abandoned your first love (2:4)
- you have fallen (2:5)
- You have some there who hold to the teaching of Balaam, who taught Balak to place a stumbling block in front of the sons of Israel: to eat meat sacrificed to idols and to commit sexual immorality. 15 In the same way, you also have those who hold to the teaching of the Nicolaitans. (2:14,15)
- you tolerate the woman Jezebel, who calls herself a prophetess, and teaches and deceives My servants to commit sexual immorality and to eat meat sacrificed to idols.(2:20)
- you have a reputation for being alive, but you are dead. (3:1)
- you are neither cold nor hot … you are lukewarm. (3:15)
- you are wretched, pitiful, poor, blind, and naked (3:17)

That is what happens to good churches. 71% of the churches are rebuked for unfaithfulness. It is extremely common for churches to go bad. The pages of Scripture make it sound to me like it is the rule rather than the exception.
Paul did something in Ephesus that he didn’t usually do – he stayed a long time. He was there 3 years teaching the people and training the elders. And at the end of those three years he made a bold prediction about that church. He gathers these godly pastors whom he had personally groomed and trained and placed in office… and predicts unfaithfulness!

Acts 20:29-31 I know that after my departure savage wolves will come in among you, not sparing the flock. 30 And men even from among yourselves will rise up with deviant doctrines to lure the disciples into following them. 31 Therefore be on the alert, remembering that night and day for three years I did not stop warning each one of you with tears. 

Paul warned each one of them individually. And not just once or twice, but constantly – over and over and over again day and night for three years. Can you imagine that? You’re in your house and there is a knock at the door and it is Paul – again – for the 500th time; and he steps in and says, “I just had to come over and warn you again - please, watch over yourself and the church. This is the Lord’s bride we’re talking about!” And you look at his face and there are tears streaming down– again.
And even after all that warning, when there is the big, emotional, tearful goodbye where all these dear, dear friends of Paul are embracing him and saying farewell and they are heartbroken over Paul’s statement that they would never see him again, Paul speaks up and predicts unfaithfulness on their part. It is not a prophecy – there’s no “thus saith the Lord.” And it is not because Paul saw some bad signs among them. If Paul knew of any movement toward unfaithfulness in any of those guys you can be assured he would have put those men out – or at least removed them from leadership. These are men who are in positions of leadership because Paul put them there. Every one of these men was above reproach, self-controlled, respectable, able to teach, mature in the faith, good reputation, proven leaders, sound in doctrine, etc., and Paul looks them in the eye and says, “Not only will savage wolves come in and rip this church apart, but even some from among your own number will rise up with deviant doctrines to lure the disciples into following them.  
How did Paul know that? As I said, it is not presented as a prophecy. Paul just knew this from experience. He had just seen this happen so many times that he could just tell them with confidence - even though there were not necessarily any signs of it yet - it was going to happen.
That means for Agape Bible Church, it is almost inevitable that this will happen. And the thought of that is heartbreaking, because Jesus Christ is worthy of a faithful wife and He paid a high enough price, He should have one.
I used to think it would be impossible for that to happen in a church with godly, mature leadership and sound preaching - until I saw it with my own eyes. And even then it took me a long time to believe it. Unless a church is especially vigilant, the normal pattern is for it to eventually be ravaged by some good leader who goes bad and twists Scripture in order to get people to follow him.
That is not to say the church will go completely bad. There are degrees of unfaithfulness. For some of those churches in Revelation Jesus had mostly praise and only a little rebuke. Their unfaithfulness was only in one isolated area.
But even for the churches that were mostly faithful, the warnings regarding their unfaithfulness were very severe. Unfaithfulness is an exceedingly serious issue, and it is critical that we do all we can to avoid it at Agape.
So how is that done? Jesus Christ is worthy of our faithfulness; so what can we put in place now that will guard us from drifting in the future?
There are no guaranteed safeguards 
None of the normal safeguards are any guarantee. Joining a denomination will not guarantee anything. There are some wonderful denominations, but even the good ones have plenty of unfaithful churches. Setting up good policies is no guarantee - there are thousands of churches with excellent constitutions that have become unfaithful. (Having excellent wedding vows is a good idea but it is no guarantee that there will never be adultery or divorce). Not even having good leadership is a guarantee (as is obvious from this passage in Acts 20).
Only vigilance will keep us from unfaithfulness
So what can we do? What does the Bible tell us about how we can be assured that we will never become unfaithful as a church? The answer to that question is simple – nothing. There is nothing you can do that will guarantee faithfulness. If there were, Paul would have done it in Ephesus. The only thing we can do is to do what Paul said to do in v.28. The grim fact is that unfaithfulness always, always remains a very real threat, and no church or individual is immune to that threat. And the sooner we become convinced of that the more likely we will be to follow the counsel Paul gave the Ephesians pastors in v.28:
 
Acts 20:28 Be on guard for yourselves and for all the flock

That is the same word Jesus used when He warned Sardis to be alert. It means to stay awake, to keep watch, to be on the alert or on guard - it is the opposite of mental sluggishness or spiritual sleepiness. 
Unfaithfulness is always a threat, and so the only thing we can do to avoid it is to have constant vigilance. The moment we rest our confidence in a constitution or an organization or a policy or an individual or anything else, the enemy will pick us off so fast we will not know what hit us. If we are going to remain faithful all the way to the end; if we are going to be overcomers and be a church that perseveres and is commended by the Lord; we are going to have to keep on guard day and night, year after year until the Lord returns. 
We are going to need to exercise the most unpopular virtue in our culture today: discernment. Space does not permit a full study on discernment at this point, but it is crucially important for our vigilance, I hope you will listen or read through the study on discernment (available for free at http://www.foodforyoursoul.net/agape_bible_church/discernment.php). The most important part of that study are parts 1-4.
Whatever you do, make sure you work hard at becoming a discerning Christian, because to be alert you have to be discerning, and the command to be alert comes over and over and over in the NT.
Urgently and frequently commanded
Mt.24:42 be alert, since you don't know what day your Lord is coming.
43 … If the homeowner had known what time the thief was coming, he would have stayed alert 
25:13 "Therefore be alert, because you don't know either the day or the hour.
Mark 13:37 what I say to you, I say to everyone: Be alert!"
Lk.12:37 Those slaves the master will find alert when he comes will be blessed. 
1 Cor.16:13 Be on the alert, stand firm in the faith, act like men, be strong.
Col.4:2 Devote yourselves to prayer; stay alert in it 
1 Thes.5:6 we must not sleep, like the rest, but we must stay awake and be sober.
1 Pe.5:8 Be sober! Be on the alert! Your enemy the Devil is prowling around like a roaring lion, looking for anyone he can devour.
Rev.3:2 Be alert 
 3 … if you are not alert, I will come like a thief, and you have no idea at what hour I will come against you.
Rev.16:15 "Look, I am coming like a thief. Blessed is the one who is alert 

A weakness for the American Church
How do you think we are doing in this area? Would you characterize the Church in our corner of the world at this time as being especially vigilant and alert and sober-minded – on guard, keeping watch? There are a lot of words people might use to describe the 21st Century American Church, but I don’t think “vigilant” is one of them. There are a lot of wonderful strengths in the Church in America in other areas, but in the area of vigilance I am afraid we probably have a lot in common with the disciples in the Garden of Gethsemane. Jesus told them to stay awake and to keep watch, and an hour later He came back and found them all dead asleep. When you think of the Church in America in general, or when you think of this church – Agape Bible Church, or when you think of yourself as an individual, do you see spiritual alertness and vigilance? 

Individual Vigilance 
Are you on your guard against the enemy?
Which of these pictures do you think best represents the church in America?

What about your own spiritual life? When you look at that last picture, are you looking in the mirror?

1 Pe.5:8 Be sober! Be on the alert! Your adversary the Devil is prowling around like a roaring lion, looking for whom he can devour.

You have an enemy who is real and who is powerful and who is vicious. If your theology doesn’t allow for the possibility that he can inflict some very real, very damaging harm on you, look again at that verse. God does not give us that warning so we can avoid being scratched. He gives it to us so we can avoid being devoured.
The enemy will attack in your unguarded hours
You are at war against a very formidable and very cunning enemy. And he is patient. He is waiting for your unguarded hours. Think about it – if you were Satan which of these guys would you go after?

Think of all the times when you fall into sin. Isn’t it mostly times when your guard is down? The most dangerous words in the Christian life are, “I can handle this. It is no big deal. I’ll be fine.”
A lot of times we are the least watchful and on our guard during the times when we know the attack will be the strongest. For example, when we watch TV. I don’t know of any force more powerful to numb your mind to the value of the grace of God than most entertainment (movies, TV shows, sports, and commercials). I don’t know of any force more powerful to intoxicate your spirit and make it unresponsive to and oblivious to the presence of God in your house. I don’t know of any force more powerful to blind your heart to the beauty of the glory of God. I don’t know of any force more able to throw water on the flames of your desire for God.
That is where the battle rages hottest, and so often that is when we are the least on our guard. We watch TV when we are tired, when we are alone, or late at night – times when our guard is down. For a long time we just got rid of TV altogether. We have it hooked back up now, but I am doing everything I can to keep our guard up. We watch only 3 shows per week. And about 20 minutes before the show comes on we gather together as a family in the living room and pray. Sometimes we sing some worship songs, and we consider some Scripture, and we pray and ask for God’s protection and His blessing on this family event we are about to undertake in watching the program. And we ask God to help us focus our minds on His glory and attributes as we watch the show and enjoy the restful time together as a family.
On my computer it is the f2 button that enables the Internet. I have a sticker on my f2 key that says, “Pray!” One of the dumbest things I can do is get on the Internet without praying first and preparing myself for battle. I do that because I have learned over the years that most of the time I am no match for Satan when I am on his turf. And if my guard isn’t up, I will fall.
Maybe for you it is not TV or the Internet. Maybe it is reading a novel, or going to the gym or going on vacation or going to work. You know what those things are in your life that leave you less able to delight in God after you’ve done them. They leave you less interested in spiritual things. They leave in a condition where it is hard to get back to delighting in the glory of God.
Another time of great danger is night time. Your mind is groggy, you are tired and weak and unguarded, and Satan just lets you have it with all kinds of evil thoughts. How often do we have victory all day long over worry, and then worry ourselves sick when we are lying in bed at night? How often do we have good victory during the day over our temptation to hold a grudge or to rehearse some offense against us, but then we lie in bed and tear that person to shreds? How many of you have righteous, holy dreams most of the time? 
Nighttime, for me, is a dangerous time. So before I get in bed at night I get on my knees at my bedside. I do that because I can’t pray in bed – my mind just gets too distracted. I kneel down and remind myself of all the wonderful things God did that day, at least one wonderful thing He did in the past, and then I beg Him for protection for the coming night.
People always pray for safe travel when they leave on a trip. I think lying in bed at night is a lot more dangerous than going on a road trip. Pray for safe travel through the night before getting into bed each night.
Be watchful! Be vigilant! Be on your guard! Be alert! We need to do that as individuals and as a church.
When we were kids playing tag we always had a base. If you touched the base, you were safe – no one could tag you. In this war there is no base. Satan can attack at any moment in any place at any time. He has no respect for anything – he will attack you with gross temptations right in the middle of your prayer time. He will attack you at night, at work, at home, in your car, on vacation… When we go on vacation and take a vacation from God and from His Word and prayer, Satan does not go on vacation. There is no base. There is only one way to keep from unfaithfulness and that is constant vigilance. 
Corporate vigilance 
So what does that look like in a church? The Lord gives us an idea in Rev.3. 
Sardis was a dead church that looked like it was alive. In fact they had a reputation for being an especially lively church. There must have been a lot of programs and ministries and a whole lot of activity and numerical growth. But Jesus came to them and said, “Despite your reputation, you are dead.”

Rev.3:1-4 To the angel of the church in Sardis write: "The One who has the seven spirits of God and the seven stars says: I know your works; you have a reputation for being alive, but you are dead.

Then the solution to all that comes in v.2.

2 Be alert …

Then, after telling them to be alert, Jesus goes on to give several other instructions. And then at the end He summarizes them all with that same word – alert.

2 Be alert and strengthen what remains, which is about to die, for I have not found your works complete before My God. 3 Remember therefore what you have received and heard; keep it, and repent. But if you are not alert, (in other words, if you don’t do all these things) I will come like a thief, and you have no idea at what hour I will come against you.  (3:2-4)

So in their case alertness meant repenting, strengthening the little good they did have but that was dying, and remembering & keeping God’s Word. Generally speaking they were a dead church. However in v.2 we find out that it wasn’t completely dead. There were some aspects that were still alive, but that were about to die, and alertness meant discovering and then strengthening those things. 
That is the way it is for a church. The church is a complex organism – like a body. And it is possible for some parts to be healthy while other parts are dying. What we need to do at Agape is to find a way to be aware of parts of our ministry that are dying, so we can strengthen them.
So how can we do that? Two things come to my mind:

1) Understand what deadness is and what life is. 
Our natural tendency is to measure everything by numbers & activity. A ministry that is getting bigger and bigger and that is very popular, we assume is thriving. But remember, Sardis had a reputation for being alive, even though it was dead. So the appearance of life is not a good measure. A ministry should be judged to be alive or dead not based on the external busyness that surrounds it, but based on the spiritual benefit that comes from it. How much is the Word of God being instilled into the hearts of people as a result of that ministry? That is the measure of life. 

2) When some aspect of the church is found to be dying (that is, it is not effectively bringing grace from God’s Word into people’s lives), strengthen it. Use the Word of God to discover what’s wrong with that aspect of ministry, and how it can become what God wants it to be.
And again, this requires a lot of vigilance. I told you our goal in this study is to structure everything we do from the principles we are learning. So somehow we need to find a way to build vigilance into the DNA of our church right from the beginning. I don’t ever want Agape to become a church were the structure is such that, when you see a problem the only real options you have are to complain or leave. When a church is set up like that you get a lot of people complaining and a lot of people leaving, but no one fixing anything.
So one structure we will set up is this: Each of the small groups will periodically makes a list of the 2 or 3 areas in the church that are most in need of strengthening. That small group will then spend some time searching the Scriptures to figure out what they can do as a group to strengthen that area, and then take that on as their ministry.
Let’s make sure we never fall asleep at the wheel as a church. Let’s make a commitment in our hearts right here and now to be a vigilant church until Jesus comes back so when He returns He finds us watching our lives and our doctrine.
Repentance
If we want to remain faithful to Christ as His bride, the first half of what we need to do is to be vigilant and alert. But what about when we do fail? How do we handle unfaithfulness in the church? How do we handle sin? That is the other half of faithfulness. And it is one of the most important questions a church can ask – “How are we going to deal with sin in our midst?” When we become watchful and vigilant and alert, we are going to discover sin in our midst.When you discover it in your life, repent. When you discover it in the life of someone else, call that person to repentance. 
And when we find it in widespread fashion in the church, the whole church needs to repent. Have you ever seen a whole church repent? I don’t think I have. Jesus called 71% of the churches in Rev.2&3 to repent, so it sounds to me like church-wide repentance should be a common thing, not a rare thing, and yet I don’t know if I have ever seen it happen. If we discover that we are guilty of some sin as a community, we need to repent as a community.
Helping one another through church discipline 
And at the individual level we need to help each other. The Lord Jesus Christ gave us very clear instructions on how to deal with sin in the church. Those instructions are found in Mt.18 and they are expounded further in 1 Cor.5 and a few other places. And the process is very simple. There are six steps.

Mt.18:15 If your brother sins against you, go and rebuke him in private. If he listens to you, you have won your brother. 

That is step one. If you become aware of some unrepentant sin, you confront that person face to face, one on one without involving anyone else. And the confrontation has one purpose and one purpose only – to persuade the person to repent. That means you have to show him his guilt – show him from Scripture that what he is doing is clearly sin, and then persuade him to renounce that sin and to be willing to give it up. Do everything you can to convince him that Jesus Christ is worthy of a beautiful, pure, faithful bride. This is something you are required by God Himself to do every time you ever see anyone in the church who claims to be a Christian and who is in unrepentant sin.
If he repents the matter is over. You have won your brother, and no one else ever needs to know about it. But what if he doesn’t listen? Then you go on to step 2.

16 But if he will not listen, take one or two more with you, so that by the testimony of two or three witnesses every fact may be established.

You go as a small group to try to persuade him to repent. But what if he still doesn’t repent? Then you move on to step 3.

17 If he pays no attention to them, tell the church.

Step 3 is for the whole church to try to persuade him to repent. When the entire church is calling you, stopping by your house, writing you letters, sending you emails, and they are all acting out of love for you – exhorting you from God’s Word to repent - showing you reasons why you should do it, warning you about consequences if you don’t, encouraging you, reminding you that you have the strength to do it in Christ - offering to help you however they can, that can have an incredibly powerful effect.
But in a few extreme cases you will sometimes get a person who will not respond even to step 3. Then what? What do you do if he will not even listen to the whole church?

17 … if he doesn't listen even to the church, let him be like an unbeliever and a tax collector to you. 

Pagans and tax collectors were shunned. If he refuses to listen even to the church, then the church is to excommunicate him and have nothing to do with him. You have no Christian fellowship with him at all until he repents.
1 Cor.5 gives us a picture of exactly what that looks like. In that chapter Paul walks the Corinthians through exactly what they should have done with the guy in their church who refused to give up his sexual sin.

2 … you should have been filled with grief so that he who has committed this act might be removed from among you.

And that is to be done as an official, public action of the church.

4 In the name of our Lord Jesus, when you are assembled, …  5 turn that one over to Satan for the destruction of the flesh, so that his spirit may be saved in the Day of the Lord. 

It is an official excommunication in which the person is handed over to Satan. He no longer has the protection of the church, and he is to be ravaged by Satan until he is willing to repent. Then in vv.9-11 he clarifies that he is not talking about shunning non-Christians who are in sin. This only applies to people who claim to be Christians.
 
9 I wrote to you in a letter not to associate with sexually immoral people--  10 by no means referring to this world's immoral people, or to the greedy and swindlers, or to idolaters; otherwise you would have to leave the world.  11 But now I am writing1 you not to associate with anyone who bears the name of brother who is sexually immoral or greedy, an idolater or a reviler, a drunkard or a swindler. Do not even eat with such a person.  12 For what is it to me to judge outsiders? Do you not judge those who are inside?  13 But God judges outsiders. Put away the evil person from among yourselves.

So, are we to be judgmental? No. But are we to discern sin? Yes, if the person claims to be a Christian. If the person refuses to repent even after you have carefully carried out the first three steps you are to officially put him out of the church and have no fellowship with him at all – not even eating a meal with him. That is step 4.
Now back to Mt.18. You might be thinking, “Where are steps 5 and 6? We’re out of verses. Verse 21 starts a new section.” Steps five and six appears back in v.15, right after step one.

Mt.18:15 If your brother sins against you, go and rebuke him in private. If he listens to you, you have won your brother. 

That is step five. The word “listen,” in this context, means to heed what you say and respond. In other words, to repent. Step five is for the person to repent. And the reason Jesus gives us step 5 right after step 1 is because the only goal of the entire process is to get to step 5. And the person can skip right to step 5 at any point in the process. If he repents right away, you are not to involve anyone else. If he repents with the two or three witnesses, you are not to ever tell it to the church. If he repents when the whole church is confronting him in step 3, you are not to put him out.
Step 5 is the goal, so as soon as it happens, you go immediately to step 6. Step 6 is implied in v.15, but then described in detail starting in v.21. Step 6 is forgiveness. When Jesus says “You have won your brother” and then just leaves it at that, the implication is that the matter is over, and you are fully reconciled. When Jesus taught this process in Luke He stated step 6 explicitly. 

Lk.17:3-4 Be on your guard. If your brother sins, rebuke him, and if he repents, forgive him. (steps 1,5 and 6).

It is not a coincidence that Peter responded to all this in v.21 by asking about forgiveness, and Jesus gave him a lengthy answer about forgiveness.

21 Then Peter came to Him and said, "Lord, how many times could my brother sin against me and I forgive him? As many as seven times?"  22 "I tell you, not as many as seven," Jesus said to him, "but 70 times seven. 

As soon as the person repents, everyone involved needs to be very emphatic about their full forgiveness of that person. He is your brother, and there should be no remaining tension in your relationship whatsoever – even if he repeats his sin over and over. Some people try to rationalize their unforgiveness by saying, “He must not have truly repented, because he keeps falling back into the same sin.” Is that a biblical attitude? Are we to question someone’s repentance if he ends up falling back into the same sin again?

Lk.17:3-4 Be on your guard. If your brother sins, rebuke him, and if he repents, forgive him. (steps one, five and six) 4 And if he sins against you seven times in a day, and comes back to you seven times, saying, 'I repent,' you must forgive him." 

If he claims to be repentant, you are to accept that as true repentance even if it happens 7 times in one day. If there is something in his actions that show unrepentance (for example, if his sin is drunkenness and he claims to be repentant but refuses to dump out the alcohol that he has in his house), then he is obviously not repentant. But if he takes whatever steps he can take in that moment but then later falls to temptation – we are not to question his repentance. We are simply to forgive him and do what we can to help him break free of his enslavement to that sin.
And if you want to get a good picture of what step 6 looks like, take a look at 2 Cor.2. In that chapter it sounds like there was a guy who had gone all the way through step 4 and was put out of the church (it may have even been the guy from 1 Cor.5); but by 2 Cor.2 he had repented, and Paul is urging the church to fully forgive him.

2 Cor.2:7-8 so now you should forgive and comfort him instead (of punishing him); otherwise, this one may be overwhelmed by excessive grief. 8 Therefore I urge you to confirm your love to him. 

Once a person has been the subject of public church discipline, when he repents the church should go out of its way to not only forgive but to pour out effusive love on the person. And they need to be very energized to comfort that person and console that person instead of punishing him further. They need to do all they can to see to it that the person doesn’t get overwhelmed with excessive grief over his sin. They need to comfort him and repeatedly affirm their love for him. That is step 6. If a church goes through the church discipline process but then step 6 doesn’t happen, you know what they did was not true discipline – it was just vengeance.