Some of those who use spiritual exercises make progress in the life of the spirit; others, using the same exercises, make no progress. To believe that their use either constitutes enlightenment, or guarantees it, is mere idolatry and superstition. To neglect them altogether, to refuse to find out weather and in what way they can help in the achievement of our final end, is nothing but self-opinionatedness and stubborn obscurantism.

The Perennial Philosophy by Aldous Huxley