Question: I don’t see how G-d is the Only One in existence—I know that I exist (“I think, therefore I am”) and I know that other people, etc. exist. However, I can accept that there’s only one all-encompassing Creator who’s eternal and can do anything imaginable (except for destroying Himself or creating another god like Himself) . . . I call this one and only god Hashem. Is this heretical?
Answer: Your point is a very good one. It is very hard to understand how God is the Only One in the universe, given that we see everything else in the universe which appears to have an existence of its own.
It is clear that we believe that God is indeed the Only One in the universe. How this can be is, at least now, beyond our comprehension. So you are in good company for being confused or unclear how this can be.
Rather, our Sages teach us, that only in the future time, after the Messiah has arrived, and a new world order, so to speak, emerges, will it become clear to us the reality of God as the Only One. It is as if we wear translucent glasses in this world, and so we can see the world, but not clearly. In the future world, those glasses will be replaced with transparent glasses, and the picture will be crystal clear. Of course, the analogy only goes so far, since we dont realize we are wearing foggy glasses—everything appears clear to us.
So, one might say, that there is a certain element of faith required to accept that God is the Only One.
Rabbi Yoel Spotts