Sermons Four Prison Walls of Withholding Forgiveness Posted on Friday, May 29th, 2009 at 2:06 pm. The Parable of the Unforgiviing Debtor (Matt. 18:21-35) Revenge (Part 1), Resentment (Part 2), Regret (Part 3), Resisting Blessing (Part 4) Part 1 | Part 2 | Part 3 | Part 4