Here is the petition that is the most needed to maintain our relationship with God.  It is the petition that helps to keep our mind and soul pure so that we can commune with Him in prayer.  Hence this petition for daily forgiveness makes it possible to be satisfied with our daily bread, and also makes it probable that He will guide us and deliver us from evil when we ask Him.

The forgiveness that we ask for is according to our debts to God.  For God has given us His laws and we have not obeyed them, we have not been righteous as He requires.  Thus, because of our sin against God, we owe Him a huge debt of consequence.  How can we pay this debt?  It is so immense, so gigantic that we will never be able to pay it back.  Therefore, all we can do is…