To me, the only odd thing here is that people think Isaac Newton is/was odd because he was interested in religion, alchemy, etc. Being a scientific "genius," isn't mutually exclusive with being interested in other things that weren't scientific.
To people with the 'Magicians Mindset' as Keynes might put it, the world has a rational soul underlying it which can be teased out by careful study of all things. If you're a Christian and start with this prior belief, then it makes perfect sense that you should expect your theological studies to inform your understanding of the natural world and your understanding of the natural world to inform theological studies. This is a mindset where metaphors and abstract connections are not of the human mind. Rather, they represent features of the territory showing us God's divine authorship of the world.
Another good book that outlines some of this is Hall's The Secret Teachings Of All Ages, which discusses the essentially Aryan (Indo-Iranian) thesis that all theological traditions discuss the same underlying esoteric doctrine which itself descends from one civilization. Having been written in 1928, Hall speculates Atlantis. (Naturally, you should take this text with perhaps more than just a grain of salt.) As far as I know the modern version of this thesis usually places the ultimate originating civilization in India.
https://www.amazon.com/Secrets-Alchemy-Lawrence-M-Principe/d...
https://archive.org/details/The_Secret_Teachings_Of_All_Ages...
Also, "The Secret Teachings Of All Ages" sounds quite similar to the perennial philosophy.
The guy was a Renaissance Man through and through. It would be weirder if a guy with his level of genius and accomplishments wasn't interested in such a wide range of subjects and only was interested in a few subjects.
And by interest I don't necessarily mean that he has to excel at everyone one of them the way he did with physics and mathematics, but rather, to be intrigued enough to study them.
A negative result is still a result.
"Every action has an equal and opposite reaction" is just the golden rule restated as a physical law. Newton starts from the assumption that the physical world follows a moral law because it was created and is animated by god and everything else follows from and is in accordance with that belief.
No, it's closer to lex talionis stated as a physical law.
Which I guess is also religious.
https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion
Translation from google: "To every action there is always opposed an equal reaction"
If the golden rule is: do unto others as you would have them do unto you and you restate that as if it has force of law then you get:
Whatever you do to others will be done to you.
And then that moral law is generalized to all things to make the physical law:
For every action there is an equal and opposite reaction.
Also, it could be argued that the use of actio (https://en.wiktionary.org/wiki/actio) implies a rational agent, not an abstract principle.
It could also be pointed out that the "law" itself is just metaphysical twaddle. There is no empirical basis for this "law" and it makes no sense at all unless taken as a principle based on established authority.
The modernized version of the law is "When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body."
The extent of revision required to make the "law" even vaguely scientific demonstrates how unscientific the original was.