Safra Det'zniuta: Chapter 4
Fourth Chapter

This chapter tells us that Atika is hidden but Zeir Anpin, who is partially hidden, is revealed in Malchut. He cannot be comprehended in His own place, but He can be comprehended in a different place. When lower man descended in the image and likeness, there were two spirits in him from his two sides, because man combines right and left: the holy Neshamah and the living Nefesh. When he sinned the left expanded from above downwards. The theme of 'two' is carried throughout the rest of this chapter, in connection with the Holy Names, the climbing scales that go up and down, Male and Female, the two equal crowns of Dalet and Vav, two men to spy secretly, two women, two who were embracing above. All these allusions to two result again in the statement that it is necessary to unite the right and the left and the central columns together, for the healing of Hashem is drawn by this unity.