Q. If Christ has forgiven our sins for eternity (Heb 10:14), and we now repent (change/renew our minds) and no longer ask forgiveness of sins, why does Christ teach us to ask “forgive our debts (sins) as we forgive our debtors”?
A. If you’re quoting from the Lord’s prayer (Matt. 6:9-13) read the next two verses. “For if you forgive men when they sin against you, your Heavenly Father will also forgive you. But if you do not forgive men their sins your Father will not forgive your sins” (Matt. 6:14-15).
The Lord was not speaking of the forgiveness that brings salvation. That forgiveness is granted on the basis of faith alone and can never be revoked.
But one of the conditions for remaining in a close relationship with the Lord is to forgive others as He has forgiven us. Doing so brings blessings in the here and now. Failure to forgive a brother who sins against us is itself a sin that puts a strain on our relationship with the Lord and can deprive us of blessings we might otherwise receive. We cannot be close to Him again until we’ve sincerely forgiven our brother. This is explained in the Parable of the Unmerciful Servant (Matt. 18:21-35).
By the way, 1 John 1:9 reminds us that even though we’ve been saved forever, we should confess each time we sin. Doing so maintains our close relationship with God.