This is really a 3 volume list of books: a text, a workbook and a Trainer's guide, that I read from continually, and have with the past 31 many years. It has become the most important spiritual messages of our time. The Course combines 21st Century psychology with non-dualistic metaphysics. https://www.youtube.com/channel/UCXpL4OXSmktqlP6_S5p5jIQ