...of a decidedly heretical nature. England was comparably free at the time, rejecting the Trinity could get you in **big** trouble elsewhere.
So? A concept is not religious just because it was thought up by a religious person. Issac Newton's theories aren't religious in nature just because he was a devout Christian (and Alchemist, but that's another matter).
To a christian who believes God is everywhere present and active in the world, why shouldn't the laws that God made for the world not reflect that fact?
There are two very bizarre phenomena in the modern world. One is that idea that one can separate science from religion, and the other that you can separate religion from science. In fact, they are everywhere at least contiguous if not overlapping, and each one develops the understanding of the other at all times. Above all though, religion has always been the primary motivator of science, even if that religion was logical error of atheism.
Newton understood this, and that is why he found alchemy plausible. He would have found Einstein even more plausible, but he didn't know him.