Reference for Leviticus 18:20

וְאֶל־אֵ֙שֶׁת֙ עֲמִֽיתְךָ֔ לֹא־תִתֵּ֥ן שְׁכָבְתְּךָ֖ לְזָ֑רַע לְטָמְאָה־בָֽהּ׃

And thou shalt not lie carnally with thy neighbour’s wife, to defile thyself with her.