Siddhis keep you from becoming enlightened. Siddhis actually keep you back. Some people, because of past lives and past experiences, as they progress on this path, they develop certain siddhis. They can … read the future, look into the past, be able to do astrology, the I Ching, become a Master of occult powers. In the Upanishads it clearly states, occult powers will keep you back for thousands of incarnations. Do not rest on siddhis. Leave the siddhis alone. Go beyond them. Go beyond everything, until there is no one left to do siddhis. To do siddhis, there has to be an entity. There has to be a person to experience these siddhis. In Advaita Vedanta, the person becomes obliterated. Therefore for whom are there siddhis? So when you see a person with great siddhis, really that person has a mind. His or her mind is still working, and they will not be free. Only when you give it all up, and you destroy the ego, the personality, do you become omnipresence. If you are everything, why do you need siddhis? Forget about siddhis.
~Robert Adams