The Lord's Prayer is a pattern prayer for all our praying, but it is also a lesson for us in forgiveness: we must forgive.
In Matthew 6, the petition, "and forgive us our trespasses as we forgive those that trespass against us" is the one petition that the Lord emphasizes above all others. It's almost as if Jesus is saying that this is the main reason for giving us the prayer in the first place! He no more says "Amen" and then he says, "For if you forgive men their trespasses, your heavenly Father will also forgive you; But if you forgive not men their trespasses, neither will your Father forgive your trespasses."
This makes perfectly good sense. It's a matter of justice, isn't it. It's not fair for us to ask God to forgive us our enormous offenses against him, if we will not forgive the offenses people have committed against us. That doesn't make it easy, but it is the fair thing.
And think of it this way: How can God forgive the sins of someone who refuses to let go of his own sins? Bitterness and resentment are sins. If you won't let go of your resentment toward someone, you are hanging onto a sin and, as David says in the Psalms, "If I regard iniquity in my heart, the LORD will not hear me." I like the way Michael Green puts it in his commentary on Matthew: "For if we are to open our hands to receive his gracious pardon, we cannot keep our fists tightly clenched against those who have wronged us. So often our prayers are nullified because there is someone we think we cannot forgive" (p. 101).
The Lord's Prayer is a model prayer for us because it reminds us that there can be conditions for God's blessings in our lives. Our salvation is ultimately all of God's grace, but within that grace, there is a place for our own responsibility, and here it is. If we want to walk at peace with God with a clean conscience, with our sins forgiven, we have to seek the grace from him and be determined to be forgiving ourselves.
It can be very, very difficult to forgive sometimes, but we absolutely must. And we may have to forgive someone over and over again, every time we remember what happened. But each time we do, we know we are doing the right thing. We also know we are doing what is good for our own souls. Plus, our friends, our families, our churches, the whole world need our prayers. It's worth giving up our foolish bitterness so we can keep the channel of prayer open. There are so many battles left to fight.
[Image courtesy of David Castillo Dominici at FreeDigitalPhotos.net.]