Longer Catechism (Orthodox) 23.401

Chapter 23 — Part II — The Lord's Prayer

Section 401. Q. How dare we call God Father? A. By faith in Jesus Christ, and by the grace of regeneration. As many as received him, to them, gave he power to become the sons of God, even to them that believe on his name: which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God. John i. 12, 13.