I missed the Matthew Bible study at my parish yesterday because my daughter was sick. I kept her home from school. I did some of the commentary work but none of the questions.
Reid's commentary on the Parable of the Unforgiving Servant in Matthew 18 is well-presented. I'd love to share it verbatim, but let me try my skills at summarizing.
You know the story. A king settles accounts with his servants. A debtor can't possibly pay back what he owes and asks for patience, not forgiveness. The king grants forgiveness. Then the servant turns around and fails to forgive or even show patience towards his fellow servant. When the king catches wind, he tortures him like he should have done in the first place.
Reid is careful to say that, like with all parables, the God-like figure is both like and also unlike God. The king has shown his servant how to obtain loyalty and respect from his fellow servants. If the first servant had fully understood the king's actions towards him, he would have imitated them. By failing to replicate the king's approach, the servant is judging it ineffective. Since the servant thinks that physical abuse is the way to demonstrate power, the king debases him in just that way.
Even though Reid thinks Matthew 18 is directed at church leadership, the same goes for us laypeople. God has forgiven us in Jesus and we ought to act with the same graciousness towards others.