We may say that Christianity is monotheistic and the Vedanta pantheistic; but we cannot make a similar assertion about Zen. Zen is neither monotheistic nor pantheistic; Zen defies all such designations. Hence there is no object in Zen upon which to fix the thought. Zen is a wafting cloud in the sky. No screw fastens it, no string holds it.
— D.T. Suzuki, An Introduction to Zen Buddhism