Leviticus 20:21-22

And if a man shall take his brother's wife, it {is} an unclean thing: he hath uncovered his brother's nakedness; they shall be childless. {an...: Heb. a separation} Ye shall therefore keep all my statutes, and all my judgments, and do them: that the land, whither I bring you to dwell therein, spue you not out.