Whenever you stand praying, if you have anything against anyone, forgive him and let it drop (leave it, let it go), in order that your Father who is in heaven may also forgive you your [own] failings and shortcomings and let them drop.
In prayer there is a connection between what God does and what you do. You can't get forgiveness from God, for instance, without also forgiving others. If you refuse to do your part, you cut yourself off from God's part. [Matthew 6:14MSG]
Seek God while he's here to be found, pray to him while he's close at hand. Let the wicked abandon their way of life and the evil their way of thinking. Let them come back to God, who is merciful, come back to our God, who is lavish with forgiveness. [Isaiah 55:6MSG]