A.T. Robertson Commentary Matthew 18:27

"And the lord of that servant, being moved with compassion, released him, and forgave him the debt." — Matthew 18:27 (ASV)

The debt (το δανιον). The loan. Common in the papyri for a loan. The interest had increased the debt enormously. "This heavy oriental usury is of the scenery of the parable" (McNeile).