Enoch - And he answered me and said unto me: 'These three have been made that the spirits of the dead might be separated. And such a division has been made 〈for〉 the spirits of the righteous, in which there as the bright spring of water.

Notes

The book of Enoch is not part of the canonical scriptures (The Bible) we know today and we don't know how accurate it is.

Some belive while Enoch is not inspired by God that it still serves as a historical book on the time before the flood. It's also quoted in the New Testament in Jude 1:14-15.

Because of this I wanted to include this book for historical reasons.

I would recommend reading the Bible first and foremost as it should be your foundation. Then if you are intrested you can take a look at the book of Enoch.