tn The expression is מִי־יִתֵּן (mi-yitten, “who will give”; see GKC 477 §151.b). Some commentators (H. H. Rowley and A. B. Davidson) wish to take this as the optative formula: “O that a clean might come out of an unclean!” But that does not fit the verse very well, and still requires the addition of a verb. The exclamation here simply implies something impossible – man is unable to attain purity.

sn The point being made is that the entire human race is contaminated by sin, and therefore cannot produce something pure. In this context, since man is born of woman, it is saying that the woman and the man who is brought forth from her are impure. See Ps 51:5; Isa 6:5; and Gen 6:5.