Then, having come forward, Peter said to Him, "Lord, how often will my brother sin against me and I forgive him; up to 7 times?" Jesus says to him, "I say to you not up to 7, but up to 70 x 7! Through this the kingdom of the heavens is like a man, a king, who wanted to settle a logue with his slaves. And he, having begun to settle was brought to him one owing about 20 million dollars. And he, not having (enough) to pay, the Lord ordered him to be sold, the wife and the children and all, everything he had, and payment be made. Having fallen then, the slave worshiped Him saying, `Be patient with me, and everything I will repay you.' And gut-wrenched, the Lord of that servant freed him, and the debt He forgave to him. And having gone out, that slave found one of his fellow slaves, who was owing him a few month's wages, and having grabbed him, he choked (him) saying, `Pay if you owe anything!' Having fallen, then, his fellow slave begged him, saying, `Be patient with me, and I will repay you.' And he was not willing, but having gone away he cast him into prison until he might pay that which he was owing. Having seen what was happening, then, His fellow slaves were greatly grieved, and having gone, they explained to their Lord all that had happened. Then, having called him forward, his Lord said to him, `Evil slave, all that debt I forgave you when you begged me; Wasn't it needful also for you to show mercy to your fellow slave, as I Myself showed you mercy?' And angered, His Lord delivered him to the torturers until he give over all that he is owing. So also My heavenly Father will do to you, if ever each one of you does not forgive his brother from your hearts.
In Lutheran circles, Matthew 18 has become known as the *church discipline* chapter, since it is cited in almost all church constitutions under that heading. This is unfortunate, since a much better title for Matt 18 would be the *great forgiveness* chapter. For these words of Jesus not only teach us about how we ought forgive others, but they also show us the source of forgiveness in the heavenly realm–from God Himself. The LORD forgives us that we, in turn, may forgive as we've been forgiven.
But forgiving from the heart isn't so easy. Peter tries to limit forgiveness to only 7 times. He thinks he's being generous, since 3 times seemed to be the OT limit. But Jesus shows him just how limited his forgiving heart was. Likewise, these words of Jesus convict you. Could you put up with someone committing the same sin 490x against you? Hardly. You'd give up on that person long before that.
So Jesus tells a parable about forgiveness, showing just how different it is in God's kingdom. While the slave in the story proves himself to be a very lousy forgiver, the King of the heavenly kingdom shows Himself to be a compassionate Lord indeed. He forgives the debt completely, without strings attached. Christ Jesus has done this also for you at the cross. Your debt paid in full, not with the King's gold or silver, but by the body of the crown prince given, and His blood shed for you on the cross.
As we look at Jesus' parable, however, there seems to be something too-good-to-be-true about it. You might think that King should at least take the slave up on his initial offer to at least try to pay back some of the enormous debt. You may expect the King to let the man and his family pay as much as they can first, or for the King to cancel most of the debt, leaving only a small amount to be repaid.
But that's simply not how your God and King operates. He doesn't expect you strive to do your part first, so He can make up the difference. He doesn't even leave you with some of your debt to be dealt with at the end. He cancels it all. He forgives you all your sins. He washes your debt-slate clean in the waters of holy baptism, cleansing your conscience, and giving you a completely clean heart. As the prophet Micah writes, "God hurls all our iniquities in the depths of the sea" in the waters of baptism.
Yet we still aren't fully convinced that a cleansed heart can be gotten for free. Even if you are willing to accept that God cleanses your heart by canceling your sin-debt in full, you may still think that you have to do something first, since it can't be so easy. Perhaps you think that it's all up to you to get the ball rolling, that you must first show God how sincere, or how worthy you are for His forgiveness.
But all the sincerity in the world is useless toward such an un-payable debt. No lender is convinced by even the greatest desire to pay if the source of income is lacking. Such it is with you. It isn't your begging of God to be merciful that merits anything. It is his compassionate nature that prompts him to remove your sin-debt from you. He gives you the gift of repentance turning you from sins toward His gracious forgiveness, as your Pastor proclaims you forgiven in the Name of the Triune God.