“If a man has an emission of semen, he shall bathe his whole body in water and be unclean until the evening.
We have here the law concerning the ceremonial uncleanness that was contracted by running issues in men. It is called in the margin (Lev 15:2) the running of the reins: a very grievous and loathsome disease, which was, usually the effect and consequent of wantonness and uncleanness, and a dissolute course of life, filling men's bones with the sins of their youth, and leaving them...
Commenting on Leviticus 15:1-18
And if any man's seed of copulation go out from him,.... Not in lawful cohabitation, nor voluntarily, but involuntarily, as Aben Ezra observes; not through any disorder, which came by an accident, or in any criminal way, but through a dream, or any lustful imagination; what is commonly called nocturnal pollution (c): then he shall wash all his flesh in water, and be unclean until...
And if any man's seed of copulation go out from him, then he shall wash all his flesh in water, and be unclean until the even. (f) Meaning, all his body.