Jewish Mysticism
Neither something nor nothing is said about Him. Not something because He certainly is! And not nothing because the prophets saw Him as an elder and sometimes as a youth. At other times they saw only the glory… This is a wondrous form that no eye has seen. Even though the angels are created without matter and are emanated, He is hidden from them… But the sefirot that are proximate [to the divine] see Him… We know that everything is contained in Him, i.e., the sefirot are emanated and no separation is appropriate.
Translated by Elliot Wolfson in Through a Speculum that Shines- Vision and Imagination in Medieval Jewish Mysticism, Princeton- Princeton University Press, 1994.