“And he would not: but went and cast him into prison, till he should pay the debt.”
Matthew 18:30 — Greek Interlinear
Church Fathers on Matthew 18:30
That none should think that the Lord had enjoined something great and burdensome in saying that we must forgive till seventy times seven, He adds a parable.
For it is customary with the Syrians, especially they of Palestine, to add a parable to what they speak; that what their hearers might not retain simply, and in itself, the instance and similitude may be the means of retaining.
30): The Son of God, as He is wisdom, righteousness, and truth, so is He a kingdom; not indeed any of those which are beneath, but all those which are above, reigning over those in whose senses reigns justice and the other virtues; these are made of heaven because they bear the image of the heavenly. This kingdom of heaven then, i.e. the Son of God, when He was made in the likeness of sinful flesh, was then like to a king, in uniting man to himself.