This is exciting stuff. Here is the Biblical formula for belief in God's existence. It is activity based, you will notice, and, to be complete, must be stated both positively and negatively.
"Through Him were all things made. Without Him there was not anything made that has been made. " John 1:3a.
Thus, God is the Be-ing who creates all being. God's existence, His very nature, is defined in His creative activity. From this we decide that God is pre-existent, or eternal, for God is the Source of which all else becomes real. From this, we can determine God's overwhelming power. Anselm put it this way, "God is that above which nothing greater can be conceived."
Since God can be posited as eternal and self-existent, we are then able to describe God as creative. That is, God is Creator of all. This is a description of God by a rehearsal of His activity, vis a vis the result of God's activity. Stated positively God's creative activity is seen from beginning to end. Stated negatively, God's creative activity is expressed from the end looking back to the beginning. This is not merely an explanation of God's nature by human accomodational language but, rather, a description of God in result of God's awesome activity in Creation, as Creator.
Then, the Biblical writers can assume the existence of God, Genesis 1:1 and work from there. The fact the creativity of God can be stated positively and negatively (all things exist by Him, nothing that exists exists except in Him) is restated in Scripture to identify God as the Natural Creator (Understood) and the Creator of Nature (Active). That is, no other Creator can be assumed, but a Creator must be assumed.
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