But if you do not forgive, neither will your Father in heaven forgive your trespasses."
Mark 11:26
Surrounding context
11:25 "And whenever you stand praying, if you have anything against anyone, forgive him, that your Father in heaven may also forgive you your trespasses.
11:26 But if you do not forgive, neither will your Father in heaven forgive your trespasses."
11:27 Then they came again to Jerusalem. And as He was walking in the temple, the chief priests, the scribes, and the elders came to Him.