Heidelberg Catechism – Lord’s Day 46
Q. Why has Christ commanded us to address God: “Our Father”?
A. That at the very beginning of our prayer he may awaken in us the childlike reverence and trust toward God which should be the motivation of our prayer, which is that God has become our Father through Christ and will much less deny us what we ask him in faith than our human fathers will refuse us earthly things.
Q. Why is there added: “in heaven”?
A. That we may have no earthly conception of the heavenly majesty of God, but that we may expect from his almighty power all things that are needed for body and soul.