In the parable of the unforgiving servant, there are some pretty harsh words for those who refuse to forgive after having been forgiven for so much.

Matthew 18: 21-22 - "Then Peter came to Jesus and asked, 'Lord, how many times shall I forgive my brother or sister who sins against me? Up to seven times?' Jesus answered, 'I tell you, not seven times, but seventy-seven times.'”