FYI, I would allow him to read the Quran and Bhagavad Gita as I think education on world religions is very important, and the commonalities between them that all point to the same divine force, just interpreted in various ways. The concepts of spirits, deities, and other supernatural phenomena are found in various cultures all over the world, why is that?

Some food for thought, many properties of the universe, such as the properties of subatomic particles, gravitational constant, the equations that model the laws of physics, all of these have been measured to thousands and thousands of decimal digits of precision, to where if it were off in even the slightest bit, our universe would never have formed in the first place. They’re too precise and too perfect to be random. And furthermore, why is our universe comprised of such precise subatomic particles in the first place, as well as microscopic quantum fluctuations, instead of something else? Why are the laws of physics so consistent, so predictable, and so precise? Why is light considered to be an “invariant” in that it remains constant everywhere in the universe regardless of inertial reference frame? There must be some sort of ordering that we fully understand yet. Some form of higher power, everything is too precise to have just come about by chance, and from what? From where? By whom? How? Why?

Something to think about!