Leviticus 18:7

• She is your mother: Incest was illegal because it disrupted families. The commands about this sin included close relatives, even if not related by blood. Incest was a serious crime because it caused competition and chaos in the family. It threatened home safety by breaking family intimacy and belonging.

• The Bible directs this command to men, even if the woman was older, like a mother. Men, especially household leaders or firstborns, had more power. This power came with the duty to use it lawfully. Men were more often the sexual aggressors in illegal unions, though not always (for example, Genesis 39:6–18).

to have sexual relations (literally to uncover the nakedness of): Similar rules in chapter 20 of Leviticus use the Hebrew word shakab (which means “lie with”). This often indicates an improper sexual relationship.

expose the nakedness of your father: The Hebrew text equates having sexual relations with your mother or any of your father's wives to having sexual relations with him (compare Genesis 35:22; 49:4; see also 1 Corinthians 5:1). The husband and his wife "become one flesh" (Genesis 2:24; compare Ephesians 5:29). These commands always emphasize honoring your parents (Leviticus 20:9; Exodus 20:12). These commands extend to other family members (see also study note on Leviticus 20:17).