Daniel,

Thank you for the question.

The difficulty underlying your question is that, in this proposition, God seems to be merely an abstraction, or impersonal, which is hard to relate to. But consider that this is only an attribute of God, a simple fact or quality, not the whole story or what we know about God. It is merely stating that all things that exist, owe their being to Him. God is ground zero on being.

However, God is not simply being, but a community of three divine Persons, which is impossible to fully grasp because we are finite and God is infinite. We know these things because Jesus revealed truths about God that were hidden. But suffice it to say that: God is what we can best describe as Father, Son, and Holy Ghost, all co-equal with each other and yet distinct.

Keep in mind that when you read St. Thomas, you may need a bit of Aristotle and Augustine philosophy and theology, to grasp what he is saying.

Peace,

Bob Kirby