David ben Solomon ibn Abi Zimra, Magen David (Munkacs, 1912), 24b-c

Jewish Mysticism
Thus you have learned that the yod is called “moon,” [as it says in the blessing of the moon] “To the moon [God] says, ‘Renew yourself, crown of splendor, for those who have been carried since birth,’ which refers to Israel who have been carried since birth. Therefore, we do not bless it except when it has an increase of light, that is, when its blemish is filled, but not in the time of its deficiency, for one does not bless over that which is a disgrace. Here I will inform you about a matter concerning which I have been in doubt since I became mature- When you look at the form of the moon when it is full you will see in it the likeness of the form of a human face in actually. Concerning this I asked the philosophers and the astrologers, but none of them knew how to explain how this form takes shape in it, for at that time it is filled with the light of the sun and it is appropriate for it to be shining and glowing completely. In my opinion this is a wondrous secret from the mysteries of nature, and it alludes to what the rabbis, blessed be their memory, the sages of truth, said regarding the image of Jacob that is engraved on the throne of glory, and the throne is the crown of splendor of which we wrote above, and Jacob is Jacob the elder, and the moon is the image of the throne, as I have written. Therefore, the image of Jacob, our father, and his icon are engraved and take shape within the lower moon. Thus, the rabbis, blessed be their memory, established [in the liturgical hymn ’el adon ‘al kol ha-ma‘asim] ra’ah we-hitqin surat ha-levanah [“He saw and established the form of the moon”]. It does not say, ra’ah we-hitqin ha-levanah [“He saw and established the moon”], but rather surat ha-levanah [“the form of the moon”]. You will not find them speaking of the form (surah) except with respect to the moon, but not with respect to the sun, and this is to allude to this secret. Understand it well.

Translated by Elliot Wolfson in “The Face of Jacob in the Moon- Mystical Transformations of an Aggadic Myth,” in The Seduction of Myth in Judaism- Challenge and Response, 235-270. Edited by S. Daniel Breslauer. Albany- State University of New York Press, 1997.