“And forgive us our debts, as we forgive our debtors?” (Matthew 6:12, emphasis added) 

“For if ye forgive men their trespasses, your heavenly Father will also forgive you: But if ye forgive not men their trespasses, neither will your Father forgive your trespasses.” (Matthew 6:14-15)

“But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.” (Mark 11:26)

“Judge not, and ye shall not be judged: condemn not, and ye shall not be condemned: forgive, and ye shall be forgiven:” (Luke 6:37)

“Then his lord, after that he had called him, said unto him, O thou wicked servant, I forgave thee all that debt, because thou desiredst me: Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee? And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him. So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses.” (Matthew 18:32-35, emphasis added)

 “. . . For unto whomsoever much is given, of him shall be much required. . .” Luke 12:48

Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them.  And when ye stand praying, forgive, if ye have ought against any: that your Father also which is in heaven may forgive you your trespasses. But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.” Mark 11:24-26) 

Therefore if thou bring thy gift to the altar, and there rememberest that thy brother hath ought against thee; Leave there thy gift before the altar, and go thy way; first be reconciled to thy brother, and then come and offer thy gift. Matthew 5:23-24