"If you forgive those who sin against you, your heavenly Father will forgive you. But if you refuse to forgive others, your Father will not forgive your sins." --Matthew 6:14-15, NLT
Jesus gives a startling warning about forgiveness: if we refuse to forgive others, God will also refuse to forgive us. Why? Because when we don't forgive others, we are denying our common ground as sinners in need of God's forgiveness. God's forgiveness of sin is not the direct result of our forgiving others, but it is based on our realizing what forgiveness means.
It is easy to ask God for forgiveness, but difficult to grant it to others. Whenever we ask God to forgive us for sin, we should ask ourselves, "Have I forgiven the people who have wronged me?"