Christian prayer rests upon the irreversible fact of the self-revelation of God in Jesus Christ and its confirmation in our hearts by the Holy Spirit. The Holy Trinity is the basis of true prayer as well as its goal. Prayer, as biblical faith understands it, is made possible by the triune [one in three] God and is directed to this God. The God of the Bible is a living God, not a philosophical first principle or a moral ideal. He is supremely personal, yet he infinitely transcends human personhood. The biblical picture of God as “heavenly father” reinforces the idea that he is loving and caring. We do not ask as beggars but as sons and daughters, since he is the Father of all by creation and the Father of Christians in particular by adoption.

—Donald Bloesch, The Struggle of Prayer