Matthew 18:33
“Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee?”
So when his fellowservants saw what was done, they were very sorry, and came and told unto their lord all that was done.
Then his lord, after that he had called him, said unto him, O thou wicked servant, I forgave thee all that debt, because thou desiredst me:
Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee?
And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him.
So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“Blessed are the merciful: for they shall obtain mercy.”
“And should not I spare Nineveh, that great city, wherein are more than sixscore thousand persons that cannot discern between their right hand and their left hand; and also much cattle?”
“Finally, be ye all of one mind, having compassion one of another, love as brethren, be pitiful, be courteous:”
“But a certain Samaritan, as he journeyed, came where he was: and when he saw him, he had compassion on him,”
“And forgive us our debts, as we forgive our debtors.”