And if he sins against you seven times in a day, and seven times in a day returns to you, saying, ‘I repent,’ you shall forgive him.

Luke 17:4

How do you forgive the one who has ripped your heart out and stomped on it, or stolen from you something that’s irreplaceable?  I know because I’ve done that.  You forgive by faith in the One who asked you to do it, trusting Him for the grace to carry through.