“There are three partners in man: the Creator, his father, and his mother” (Kiddushin 30b).
“Right” is called “father,” who gives the white. Man should give an awakening from below, since this is the Kli [vessel], meaning the lack. This is the meaning of “As the advantage of the light from within the darkness.” Mother gives the red, meaning the “left,” meaning a red light, when we see that we cannot walk on this path. This is called “the left rejects,” when he sees that he is being rejected from the path of reaching the Creator.
Conversely, “The right pulls near,” when he believes that he can walk, and he is content with whatever grip he has on Kedusha [holiness], and he thanks the Creator.
When he has “right” and “left” and he sees the distance between them, he comes to the state of “essence,” when he comes only to purify. However, he cannot. At that time, the Creator gives the soul, and then he achieves the degree of “man.”