Yes, the teachings of ACIM are so deep that I always get a new insight every time I re-read the text. I've been studying it for 1 year and I'm on lesson 91 of the workbook now. I've studied other things before ACIM like Eckhart Tolle's teachings, Advaita Vedanta, Buddhism, Taoism, Krishnamurti's teachings, Occultism and modern spirituality but ACIM just seems to have the best parts of all of them. The Course seemed too hard for me to understand it at first and I put on effort to understand and practice it unlike some other teachings which seem easy. But I have been rewarded with peace and understanding that keeps getting better and I'm not even halfway through the workbook yet. So far no other teaching has satisfied me as much as ACIM.