Deuteronomy 27:22

The nakedness of thy sister, the daughter of thy father, or daughter of thy mother, whether she be born at home, or born abroad, even their nakedness thou shalt not uncover.

And if a man shall take his sister, his father's daughter, or his mother's daughter, and see her nakedness, and she see his nakedness; it is a wicked thing; and they shall be cut off in the sight of their people: he hath uncovered his sister's nakedness; he shall bear his iniquity.

And it came to pass after this, that Absalom the son of David had a fair sister, whose name was Tamar; and Amnon the son of David loved her. And Amnon was so vexed, that he fell sick for his sister Tamar; for she was a virgin; and Amnon thought it hard for him to do anything to her. But Amnon had a friend, whose name was Jonadab, the son of Shimeah David's brother: and Jonadab was a very subtil man. And he said unto him, Why art thou, being the king's son, lean from day to day? wilt thou not tell me? And Amnon said unto him, I love Tamar, my brother Absalom's sister. And Jonadab said unto him, Lay thee down on thy bed, and make thyself sick: and when thy father cometh to see thee, say unto him, I pray thee, let my sister Tamar come, and give me meat, and dress the meat in my sight, that I may see it, and eat it at her hand. So Amnon lay down, and made himself sick: and when the king was come to see him, Amnon said unto the king, I pray thee, let Tamar my sister come, and make me a couple of cakes in my sight, that I may eat at her hand. Then David sent home to Tamar, saying, Go now to thy brother Amnon's house, and dress him meat. So Tamar went to her brother Amnon's house; and he was laid down. And she took flour, and kneaded it, and made cakes in his sight, and did bake the cakes. And she took a pan, and poured them out before him; but he refused to eat. And Amnon said, Have out all men from me. And they went out every man from him. And Amnon said unto Tamar, Bring the meat into the chamber, that I may eat of thine hand. And Tamar took the cakes which she had made, and brought them into the chamber to Amnon her brother. And when she had brought them unto him to eat, he took hold of her, and said unto her, Come lie with me, my sister. And she answered him, Nay, my brother, do not force me; for no such thing ought to be done in Israel: do not thou this folly. And I, whither shall I cause my shame to go? and as for thee, thou shalt be as one of the fools in Israel. Now therefore, I pray thee, speak unto the king; for he will not withhold me from thee. Howbeit he would not hearken unto her voice: but, being stronger than she, forced her, and lay with her.

And one hath committed abomination with his neighbour's wife; and another hath lewdly defiled his daughter in law; and another in thee hath humbled his sister, his father's daughter.