There are a number of ancient codes of law, of which the most frequently instanced is the Babylonian Code of Hammurabi. It has been stressed that the ruler Hammurabi was bringing up to date a corpus of common law which had long before his time been codified by Libit-Ishtar of Isin, by Ibi-Sin and by Ur-Nammu of Ur; and by earlier rulers of Sumer, as well as by Hammurabi's own ancestor, Samu-la-ilum of Babylon. As one example Ur-Nammu, a king of the third dynasty of Ur, dates to something in excess of two thousand years before Christ. There are provisions in the Libit-Ishtar law code for the penalization of extra-marital coitus. Middle Assyrian laws include the following - "If he has kissed her - the wife of another - they shall draw his lower lip along the edge of a blade and cut it off." In the Code of Hammurabi a man might divorce his wife at will but must restore her dowry and provide maintenance. Both parties to adultery were liable to drowning; incest was punished by death or exile seduction was punished by fines; sodomy is not mentioned. The later Hittite Code, centuries after Hammurabi but deriving from his code, is generally said to show a marked ethical advance. For instance private revenge, not uncommon in old Babylonian law, is only allowed in one case - where a husband catches his wife in adultery: if the wronged husband thereupon kills both his wife and her lover he is guiltless in the eyes of the law; but if he does not act at once the moment of just vengeance is passed and he must then have recourse to lawful procedures.