Leviticus 18:15

18:15 You must not have sexual intercourse with your daughter-in-law; she is your son’s wife. You must not have intercourse with her.

Leviticus 20:12

20:12 If a man has sexual intercourse with his daughter-in-law, both of them must be put to death. They have committed perversion; ¹  their blood guilt is on themselves.

Leviticus 20:17

20:17 “‘If a man has sexual intercourse with ²  his sister, whether the daughter of his father or his mother, so that he sees her nakedness and she sees his nakedness, it is a disgrace. They must be cut off in the sight of the children of their people. ³  He has exposed his sister’s nakedness; he will bear his punishment for iniquity. ⁴ 

[20:12]  ¹ tn The Hebrew term תֶּבֶל (tevel, “perversion”) derives from the verb “to mix; to confuse” (cf. KJV, ASV “they have wrought confusion”).

[20:17]  ² tn Heb “takes.” The verb “to take” in this context means “to engage in sexual intercourse,” though some English versions translate it as “marry” (e.g., NIV, NCV, TEV, CEV).

[20:17]  ³ tn Regarding the “cut off” penalty, see the note on Lev 7:20.

[20:17]  ⁴ tn See the note on Lev 17:16 above.