5. If you don't care about the Bible, I strongly recommend the Tao Te Ching. Probably the most succinct, KISS philosophy and spirituality book ever written in the history of mankind.
To misquote Alan Watts, all other religions are for people that need the Tao explained with too many words.
My favourite version to start with, and even more succinct than the original, is Ron Hogan's https://terebess.hu/english/tao/ron.html then you can move on to fancier translations.