To think of God as a severe judge with whom sinners find no mercy, but of whom they can expect nothing but wrath, is altogether erroneous. This is not the case, though the law teaches nothing else of God. For the law speaks of sinners who do not desire and do not hope for any grace. But those sinners who acknowledge their sins, repent of them, and wish that they had not offended God — who mourn and lament that their lives have been in opposition to God and His commandments, and therefore ask for mercy — shall find mercy, as is here testified. The reason is that God is a merciful God and has a paternal heart. He has pity on us in our misfortune and is moved with compassion, as He declares by the prophet: “Have I any pleasure at all that the wicked should die? saith the Lord God: and not that he should return from his ways, and live?” Therefore when He finds you to be desirous of divine grace, and to hate sin and abandon it, He will cheerfully forgive your debt and show mercy unto you; as we here learn from the servant who acknowledges his debt and asks for mercy.

But as regards the means by which God will be gracious, the Gospel informs us of this in other places; namely, that the Son of God, our dear Lord Jesus Christ, took pity on poor sinners, took their sins upon Himself and paid their penalty by His death. Whoever now trusts in the Lord Jesus and in His death, has gained the good will of God, so that He can neither be angry nor punish. For aside from this He has a heart full of compassion and is moved by our misery. For this reason He of His own accord promised, as soon as Adam and Eve had fallen into sin and death, that the devil should be divested of his power by the seed of the woman.  (Luther’s House Postil, Sermon for the Twenty-Second Sunday after Trinity, Volume 3, p. 867)

That is, among Christians, forgiveness of sins shall have no measure and no end; one shall forgive the other always and beware of taking revenge; for this belongs to God alone, and His majesty and power we should never interfere with. This the parable treats of at some length, the reasons for which we will hereafter collect and notice one after another….  For the command concerning forgiveness of sins we should never apply to kingdoms of this world, in which offices and persons are not alike, but where one has always power and command over the other. Here malice is not to be tolerated nor are people to be allowed to do what they please; but misconduct must be punished and people must be admonished to live honorably and righteously.

It is not designed here to teach that a father should forgive his children everything and over look their rascality. He should punish, and for give nothing. So master and mistress and the temporal magistrate should not forgive their servants and subjects their misdemeanor, but punish them. For it is the wicked habit of the world to grow worse and worse the more its transgressions are overlooked; and if children do not want to be trained by father and mother, they must be trained by the executioner, who has to put an end to their wantonness.

Therefore this command does not pertain to the kingdoms of this world, where persons and offices are not alike, as was said before, but to the kingdom of heaven, in which we are all alike and have but one Lord, who is to be enjoyed by all. This “kingdom of heaven” begins here on earth, and is otherwise called the Christian Church on earth, in which God reigns by His Word and Spirit.  (Luther’s House Postil, Sermon for the Twenty-Second Sunday after Trinity, Volume 3, p. 864)

We should therefore follow the example of the nobleman and apply to Christ for counsel and help in all our troubles. It is an easy matter for Him to help us in our distress; He needs but to speak the word and we are delivered. He is besides very willing to help us. The nobleman is in great haste and wants to avoid every delay, but the Lord is in still greater haste, and is not willing to leave the son of the nobleman in danger, until He and his father could reach him, but heals him at once even at a distance, and at the very moment when He said to the father: “Go thy way, thy son liveth.” Thus the Lord Jesus is no doubt willing to help us, if in all confidence we ask Him. He was sent upon earth for the purpose of delivering us from sin, death and the tyranny of the devil, and to translate us into the eternal kingdom of God. For this purpose the Father, our merciful God in heaven, has sent Him, and for this purpose alone did He come.

Whoever therefore desires and seeks help against sin and death, shall surely find it, as we here learn from the nobleman, who merely sought bodily help. How much more willing will not the Lord be to help us out of a far greater danger and when we are in far greater need of His help when our eternal salvation is at stake? (Luther’s House Postil, Sermon for the Twenty-first Sunday after Trinity, Volume 3, p. 855)