A.T. Robertson Commentary Matthew 18:35

"So shall also my heavenly Father do unto you, if ye forgive not every one his brother from your hearts." — Matthew 18:35 (ASV)

From your hearts (απο των καρδιων υμων). No sham or lip pardon, and as often as needed. This is Christ's full reply to Peter's question in 18:21. This parable of the unmerciful servant is surely needed today.