Religion

Let's take a look at Genesis, Chapter 1, verse 1. For nostalgia's sake, i'll quote from the KJV

1 In the beginning God created the heaven and the earth.

2 And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the water.

So everything was formless, empty, and dark. God couldn't see, so he made some light.

Now, try to envision such a situation from a 11th or 12th century perspective. Where was everything? It's not a stretch to imagine that it was all packed into a tiny space, waiting to expand into the actual unverse instead of a black dot in the void.

That's one of the possibilities. Maybe the most likely one.

So, God figuratively poked the little dot with his stick and it ended the equilibrium and everything happened, expanding so fast you can't even imagine it. A flash of light, too, might have been part of such an event, since enormous energy would have been released in the explosion.

Your ancient Jewish philosopher might have seen it that way as a possible explanation for Genesis 1: 1-3. Maybe God took his stick and stirred up the mess to try to sort it out. I have no freaking idea.

Or, maybe there wasn't any God, and the thing just spontaneously expanded into the universe. That seems even more likely, since where did this God come from and where did he get that stick?

Imagination, trying to fill in the gaps in the story in some way. The old guy's sitting around, scratching a flea bite on his arse, and it comes to him.

Once again, the initial premise is that God exists. Ignore that, and it doesn't matter. The Universe is. It seems to have expanded from a point source. The trouble is that the Genesis account doesn't stop there. It immediately has God stirring things around with his stick, making stuff and critters. There's much more to creation that the initial moment. Maimonides just imagined one possible scenario

Really, it's all just part of a lot of Jewish philosophers over the centuries trying to interpret Genesis in one way or another. There are many stories.