When Jesus taught us to pray, we are to forgive OTHERS as He forgives us. So Jesus immediately recognized that we need to forgive others.
We have to practice forgiving other people. When we forgive others, we release them from our own bitterness, not God’s accountability.
If we don’t release bitterness, it could destroy our lives. As difficult it is for us to forgive others, to that degree we learn what it cost God to forgive us.