If we are the product of random evolutionary chance, if natural selection shaped us (which probably means a bias toward fast decisions that are probably right, rather than for slow decisions that are provably correct[1]), then it's really hard to see why math (this game we play in our heads) should necessarily have a deep connection with the rules governing the physical world.
On the other hand, if there is a God, if God is a He rather than an It, if He created the world, and if He also created humans in His likeness (sharing something of His nature), then it becomes much easier to see how there can be a valid correspondence between how we think in our heads and how the external universe works.
[1]: Darwinian survival is often a real-time problem: The right answer, too late, means you still die. A fast answer with a reasonable probability of being right beats a slow answer that is guaranteed to be wrong simply by being slow.
It seems to me you are confusing how humans think and how the physical world is governed. Humans may make shortcuts that have evolved through evolution, but the physical laws need not have anything to do with that and may in fact be better described by abstract mathematics. I do not agree that speculating about god makes this any easier to reason about.
On the other hand, if there is a God, if God is a He rather than an It, if He created the world, and if He also created humans in His likeness (sharing something of His nature), then it becomes much easier to see how there can be a valid correspondence between how we think in our heads and how the external universe works.
[1]: Darwinian survival is often a real-time problem: The right answer, too late, means you still die. A fast answer with a reasonable probability of being right beats a slow answer that is guaranteed to be wrong simply by being slow.