Midrash for Leviticus 19:20

1) (Vayikra 19:20) ("And a man, if he lie with a woman, a lying of seed, and she be a maidservant, bound to a man, and redeemed she has not been redeemed, or freedom not been given to her — there shall be censure; they shall not die, for she was not freed.") "a man": to exclude a minor. I might think that I exclude one older than nine years and one day (even though he might be potent); it is, therefore, written "And a man" (connoting inclusion).

2) "if he lie with a woman": to exclude a minor (less than three years and one day, who is not fit for intercourse). "a lying of seed": to exclude peripheral (unconsummated) intercourse. "and she be a maidservant": I might think that Scripture is speaking of a Canaanite maidservant; it is, therefore, written "and redeemed," (which cannot apply to a Canaanite maidservant). If "and redeemed," I might think that she was entirely redeemed; it is, therefore, written "she was not redeemed." How is this to be understood — "redeemed and not redeemed"? Scripture is speaking of one who is half-maidservant, half-freed woman and betrothed to a Hebrew manservant. These are the words of R. Akiva. R. Yishmael says: Scripture is speaking of a Canaanite maidservant who is betrothed to a Hebrew manservant. If so, how is "redeemed she has not been redeemed" to be understood? Scripture speaks in the language of man. R. Elazar b. Azaryah says: All of the arayoth (forbidden women) have already been stated (to be free women), so that this one, which remains, must be half-maidservant, half-freedwoman, who is betrothed to a Hebrew manservant. Others say: (Scripture is speaking) of a Canaanite maidservant betrothed to a Canaanite manservant.

3) "and redeemed she has not been redeemed": through money or its equivalent. Whence is (the possibility of redemption by) writ (of emancipation) derived? From "or freedom not given to her," and elsewhere (Devarim 24:3): "And he shall write to her a writ of divorce" — Just as there, a writ; here, too, a writ. This tells me only that money effects half- (redemption [viz., "and redeemed she has not been redeemed"]), and that a writ (of emancipation) effects complete (redemption). Whence is it derived that a writ, too, can effect half-redemption? From "and redeemed she has not been redeemed, or freedom not been given to her" — Just as money can effect half- (redemption), so, a writ.