No, not "the all," just all. Meaning that we cannot speak about "being in general" because there are two distinct *kinds* of being: Creator (infinite, eternal, unchangeable, self-existent, etc) and his creation (finite, temporal, changeable, dependent). God is not like us only "more so," we're not on the same scale at all. What makes the creature differ from his creator is not merely a matter of *degree*.
Look at what Aquinas says about univocal, equivocal, and analogical knowledge. That gets at it a bit too.