"Forgive us our tresspasses as we forgive those who tresspass against us who have repented."
And I personally don't believe it's implied.
When we pray, "Forgive us our trespasses," we are being repentant for having tresspassed against God.
When we pray, "As we forgive those who have tresspassed against us," we are creating a simile between God's forgiveness and ours. The simile is completed in this way:
As God forgives us our tresspasses when we are repentent, so must we forgive those who have tresspassed against us when they are repentent.
Or, to put it another way, as we forgive those who tresspass against when they are repentent, so do we ask God to forgive us our tresspasses when we are repentent.
The properties of the simile are commutative.
