One of the oldest ideas about God is that he is an I not an it. This means, that God can only be found subjectively, since there is no third person God. For example, in the Jewish Bible, 'I am that I am' is given as a description of God, and in the NT, we have 'before Abraham was, I am'.
In fact, 'I am' has sometimes been given as a definition of God. For example, in the Brihadaranyaka Upanishad, you find this: "In the beginning this [universe] was the Self alone… He [the Self] reflected and saw nothing but the Self. He first said, 'I am He'. Therefore He came to be known by the name aham ['I']."
However, for various reason, Christianity has not taken to this, with the exception of various mystics, and they have persevered with a kind of objective set of proofs or arguments, which to my mind, is doomed. So they are forced to argue for God as an object, or in the third person, as if God was located in Alpha Centauri.
Hinduism offers an interesting comparison, since Brahman (ultimate reality), is distinguished from Atman, (soul or self), but in some schools, Brahman is Atman. This is more like God as I or Self.