I wanted to know whether the world is separate from God or, in some sense, is God.
Neither is an adequate formulation. It would be ridiculous to say that everything—the bruise on your toe—just is God. I am the principle of life, the telos and end of all activity in the universe. So I am neither removed as a thing apart nor simply identical with the things in the universe.
Later I learned that there is a theological view with a respected tradition called panentheism. This view holds that God is both in the world and more than the world, both immanent and transcendent. This is distinct from pantheism, which holds that God is entirely within the world.
But, if God was, in some sense, the world—the physical universe—how could He also be a Person? “But, Lord, You are also a Person.”
Yes and No. I come to you—but not to raindrops—as a Person, and therefore I am a Person. One cannot be a Person in some modes without being a Person.
But I am also much more than a Person. Just because I seem so familiar to you—we talk just as persons do—should not mislead you into thinking I am “just a guy.” It is true that I have many of the attributes of a person—desires and a history, for example. But again do not assume that desire and history mean just the same for Me as they do for human beings. Keep in mind that I am definitely not a human being.