Kabbalah zu Bereschit 1:6

Another correction for the sign of the Brit is also by dealing with Torah, as we explained above where we quoted the Tikkunei Zohar (67th Correction) that whoever damages the soul can correct himself with studying Torah and the six orders of the Mishnah: One who enters his seed in a Niddah, maidservant, Cutite or a prostitute, it is like he mixed what the Creator separated, as it says ““And let it divide water from water” (Genesis 1:6), which are the waters of Niddah and waters of purity. One is forbidden and one is permitted; one is proper and one is disqualified; one is defiled and one is pure. These are the six orders of the Mishnah to separate between good and bad, which Adam and the generations that followed mixed together. Also look in the Tikkunei Zohar in the 46th Correction.