…when men say that we know God only as He is revealed in Jesus, they are denying all real knowledge of God whatever. For unless there be some idea of God independent of Jesus, the ascription of deity to Jesus has no meaning. To say, “Jesus is God,” is meaningless unless the word “God” has an antecedent meaning attached to it…We are not forgetting the words of Jesus in the Gospel of John, “He that hath seen me hath seen the Father.” But these words do not mean that if a man had never known what the word “God” means, he could come to attach an idea to that word merely by his knowledge of Jesus’ character. On the contrary, the disciples to whom Jesus was speaking had already a very definite conception of God: a knowledge of the one supreme Person was presupposed in all that Jesus said. But the disciples desired not only a knowledge of God but also intimate, personal contact. And that came through their intercourse with Jesus. Jesus revealed, in a wonderfully intimate way, the character of God, but such revelation obtained its true significance only on the basis both of the Old Testament heritage and of Jesus’ own teaching. Rational theism, the knowledge of one Supreme Person, Maker and active Ruler of the world, is at the very root of Christianity.
(“Christianity and Liberalism,” copyright©2009, pages 48-49)