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I have a friend who is very interested in learning meditation and wants me to recommend him a book, but there does not seem to be any books that are exclusively about meditation for beginners by Samael.

I know if I recommended him a book from Samael like the great rebellion or revolutionary psychology it might be a bit too heavy reading, too fast, for someone who has never been introduced to the various teachings, or someone who has never even considered looking into spirituality at all.

What are some more basic, or beginner books about practical meditation practices and techniques that are from other authors, that are still in line with the teachings?