Concerning the shade. On the night of Hoshana Rabbah (the seventh day of the Feast of Tabernacles), it is a custom that each one examines himself to see if he has a shadow, and then he is certain that he will have abundance (Shaar HaKavanot (Gate of Intentions), Sukkot Commentaries, 6-7). The shade implies clothing, the clothing in which the Light dresses.
There is no Light without clothing, since there is no Light without a Kli (vessel). And according to the measure of the clothes, the Lights increase and multiply. And when one loses the clothing, the Light that belongs to that clothing is proportionally absent from him.
This is the meaning of truth and faith. Truth is called “Light,” and faith is called “Kli.” This is the meaning of “the Creator and Divinity,” and the meaning of “Let us make man in our image,” and “Surely man walketh as a mere image.” Man’s walk depends on the Tzelem (image), meaning on faith. And this is why on Hoshana Rabbah one should see if one’s faith is complete.
And why do we call the worlds Above Tzelem? After all, Above, there is no weight of faith? However, what appears to us as dryness is a great Light Above, except we call that name “Above” because it appears to us as a shade, and we name Above after the lower one.
Bina is called “faith,” which is the Light of the Awzen (ear), meaning hearing. Hochma (wisdom) is called seeing, which is a Light that comes into the vessels of reception, considered eyes.