To Plead the Fifth

God's children ask their heavenly Father for the forgiveness of their sins. 

Q. What is the fifth petition in the Lord's Prayer? 

A. And forgive us our debts, as we also have forgiven our debtors. 

• forgive -- take away the sins
• our debts -- we should be praising God and obeying him. When we do not, we are in his debt.

That is: 

For the sake of Christ’s blood, do not impute to us, wretched sinners, any of our transgressions, nor the evil which still clings to us, 

• Christ's blood -- this is the ground, the basis, the reason, that Father forgives our sins.
• impute -- charge to our account, deposit to our account 
• wretched sinners -- unhappy, dissatisfied, lonely, alienated — man separated from God, from others, from creation and from himself.
• evil which clings to us -- our fallen nature; original sin, and also all those sins which we still do in the weakness of our human nature.

as we also find this evidence of Thy grace in us that we are fully determined wholeheartedly to forgive our neighbor.

• evidence of thy grace -- our being able to forgive others is not because of our own goodness and inner kindness but comes out of God working his grace in us
• wholeheartedly forgive -- forgiveness is not a matter which can be done half way.

For the Bible Tells Me So...

Psalm 51:1 -- According to thy abundant mercy blot out transgressions. 

Matthew 6:14,15 -- For if you forgive men their trespasses, your heavenly Father also will forgive you; but if you do not forgive their trespasses, neither will your Father forgive your trespasses. 

Matthew 18: 21-35 -- Then Peter came up and said to him, "Lord, how often shall my brother sin against me, and I forgive him? As many as seven times? Jesus said to him, "I do not say to you seven times, but seventy times seven.".... [read the parable that follows this.]

The Heidelberg Catechism Lord's Day 51