Zohar Hadash, 122a.

Jewish Mysticism
That voice goes out from one end of the world to the other, it ascends and descends, it goes and stands, no eye has the power to see it. When it is hidden it is revealed, and when it is revealed it is hidden. By means of the closing of the eyes it is seen, and through the closing of the ears it is heard. It is not known until it is summoned to the table of the truly righteous to be eaten.

Translated by Elliot Wolfson in Through a Speculum that Shines- Vision and Imagination in Medieval Jewish Mysticism, Princeton- Princeton University Press, 1994.