I am doing devotions through Luke, and read Jesus' teachings on what to do if someone sins against you. Jesus teaches that if they sin against you (against you is assumed here, because you are to one forgiving the person):
1. Rebuke him.
2. If he repents, forgive him.
3. If he sins against you seven times in a day and repents seven times, you MUST forgive him.
I think the core of Jesus' teaching here is to get to the hearts of the hearers. He says, "Pay attention to yourselves!" In other words, your ability to do this will reflect your heart condition. If you have a good heart, you will be able to do this, and will be all about reconciliation and harmony. If you have a bad heart, this teaching will seem outrageous, and you may be tempted to minimize the word "must" in verse 4.
That is why you see the response the apostles give, "Increase our faith!!!!!!" In other words, "This stuff is hard Lord, we need your help!"
My possible objection:
I hope I am not justifying things here, but it did get me thinking, "What about the guy who knows religious jargon and who uses words in order to get his way? Certainly he could say, 'I repent.' And just like that, we HAVE TO forgive him and pretend nothing happened?"
My second objection:
What if he says he repents but you know his heart is not in it? Of course we can forgive him, but do we let down our guard too?
So, I got to thinking, what does the word repent mean? In the world it means:
1. "I am sorry I got caught"
2. "I am sorry you feel I did something bad"
3. "I am sorry for doing this"
4. To turn and go in a different direction. OR
5. And this is what the biblical meaning is:
A. To repent: meta-noese
B. In this passage it is in the aorist tense, which does not give a time (past,present,future-per-se) but does have a sense of a point of action. What that means is that this person comes up to you, and describes a certain point, a certain time or situation of sin against you.
C. According to Thayer & Strong, to repent means to change your mind for the better. To HEARTILY amend with ABHORRENCE of the former direction.
The problem is that it is easy to tell people that you repent. The hard thing to do is to be filled with such dissatisfaction and grief over what you have done that you beg the person to forgive you. The latter person is easier to forgive. And this latter person is who Jesus is talking about here.
So, if you brother sins against you, rebuke him (confront him) ("Hey Bob, when you said that to me, it really hurt and attacked me as a human").
If he comes up to you convicted, "Oh man, I am so sorry for doing this! You were right, I was SOOOO wrong. I won't do it again. Please please forgive me, and how can I make it up to you?" (Or something like that).
Then say, "Yes, Bob, I agree. But I forgive you buddy."
And you, as a believer continue to forgive, just as in Christ, God forgave you.
But what if Bob says, "Sorry you feel that way. Will you forgive me?" And doesn't own it?
I think it is okay to say, "What do I need to forgive you for?" And in your heart forgive, but don't officially forgive him until he does #5.
Anyhow, that is how I see this whole passage going down.