It is narrated from Hazrat Sahl (may Allah be pleased with him) that Hazrat Uwaymir (may Allah be pleased with him) once came to Asim bin Adi (may Allah be pleased with him) and said, "Ask the Noble Prophet (peace and blessings be upon him) about this issue: if a man finds another man with his wife and kills him, will he also be killed in retaliation, or what will be done with him?" Asim (may Allah be pleased with him) asked the Noble Prophet (peace and blessings be upon him) about this issue, but the Noble Prophet (peace and blessings be upon him) did not like this question... Then the narrator mentioned the entire hadith and said that before the command of the Noble Prophet (peace and blessings be upon him), he had already separated (divorced) his wife, and this became common among those who perform li'an.