Nefesh HaChayim, Reb Itzele's Long Annotation

From that moment onward, all of the rectifications and the drawing [down] of the brains, to couple so as to express their actions in the world, that’s the second mating, which is dependent on his actions. And their order is therefore tzadiq, lamed, mem518The opposite order of the first mating. And from this you’ll understand the matter in its root in the supernal worlds.