> Except that Christianity inherited this philosophical concept of a rational and predictable world, and the concept of natural laws from Greek philosophy, which was thoroughly pagan.

Except that Greek philosophy was not pagan at all. Greek (and Roman) religious practice was pagan (and polytheistic), but Greek philosophy was 'monotheistic', especially Aristotle (e.g., Unmoved Mover) which was key in forming Christian metaphysics.

By the 1200s God as a rational actor was near the centre of Christian thought:

* https://commons.wikimedia.org/wiki/File:God_the_Geometer.jpg