So here's an idea to tug at your brain for a bit, if you like. Most Christians -- and many other religions which feature a supreme being -- say that God, or whatever name they use, is infinite.
In Christian tradition, we also say that God's attributes are infinite. God is described as both omniscient (all-knowing) and omnipotent (all-powerful). That combination leads to some head scratching when we consider suffering in the world, but that's not what I wanted to bring up here. Those phrases, all-knowing and all-powerful, are another way of saying infinitely knowing and infinitely powerful.
When we talk about God, we usually use those "infinite" words to mean that there are no limits to those qualities. There are no limits to God's knowledge, there are no limits to God's power, there are no limits to God's love, and so on. Although it's tough to actually conceive of what kind of knowledge, power, love or whatever that might imply, the concept is not impossible to grasp.
But what does it mean to say God is infinite? When we usually talk about infinity, we treat it like a really huge number, saying things like "double infinity" or "half infinity," even though those phrases really don't mean anything. Infinity is a concept rather than just a big number, which means it can't be doubled or halved or otherwise processed by mathematical operations. How do you double "everything that is?" If somehow you manage to do that, you still have everything that is, which means you still have infinity.
At the other end of the math realm, the concepts of unity (one) and nothingness (zero) work similarly. If you have one thing and you take away half of it, you still only have one thing, even though it's a smaller thing than it used to be. If you have nothing and you square it, you still have nothing.
Mathematicians have spent some time trying to figure out infinity, and as Stephen Webb notes in this article from First Things back in March, they may have a better handle on what it would mean to say God is infinite than Christians do who use the phrase. I think some of that may be because they are simply exploring infinity as a concept, while we Christians are trying to understand something about a being who is infinite, rather than just the concept itself. And some of it is probably because we spend time getting Ten Commandments monuments placed in public spaces instead of thinking about their Author.
Either way, the Incarnation or self-limiting of God into the person of the human being Jesus of Nazareth suddenly seems like quite a helpful move on the part of God. Until you start trying to think of how Jesus is both a limited human being (fully human) at the same time he's the unlimited second person of the Trinity (fully divine). But maybe that's for another time.