Night...
That light radiated from the midst of darkness hewn by truncheons of the Concealed of All, until a single secret path was carved by the hidden light, leading to darkness below, where light dwells. Who is darkness below? The one called Night, of whom is written: Revealing depths out of darkness.
~Zohar 1:32a (Pritzker Edition, Book 1, Pg. 194-195)
Rabbi Yitshak said, "Until now the male was in light; now the female is in darkness, reflecting its light. Later they join together, becoming one. How are they differentiated, distinguishing light from dark? Rungs differentiate, yet both are as one, for there is no light without darkness, no darkness without light. Though one, they diverge in color; even so, they are one, as is written: day one.
~Zohar 1:32a (Pritzker Edition, Book 1, Pg. 196)
The secret path is Yesod, Foundation, through which light comes to the Shekhinah, Malkuth. Day is Tipherah, Beauty, with is also Ze'ir Anpin. Night is the Shekhinah. She has no light of her own, but reflects the light of Tipherah. Night and Day, evening and morning, together are the first day. It is in their union that the fullness is found.
I've talked before about the Darkness being the fire of Geburah, the fire of Judgement. Shekhinah comes from the left side, the side of Judgement (which is also the feminine side, which she is). That's something to always remember. She contains all the Sephiroth, as all things do, so there is Mercy as well as Judgement in her, but she comes from the side of Judgement. This is the fire that came from heaven to burn up offerings that were acceptable to him in the days of the Tanahk (the Jewish Bible, the Christian Old Testiment). Shekhinah is harsh and can be deadly, not some tame force. She is creation and destruction. This is the presence of G-d on earth. This is the force within each one of us, the Power within us. This is G-d Herself.
FFF,
~Muninn's Kiss