Both the Khalif and Nasir were of exceptional beauty, of about the same age, and living in close intimacy,—so close as to provoke the scandalous comments of censorious tongues. It seems that Osama was the first to draw attention to these evil rumours. The Khalif had presented Nasir with the fief of Qaliub immediately north of Cairo, and in the presence of his father and Osama Nasir announced this in the words, “Our master has given me the province of Qaliub”: at which Osama remarked, “That is not splendid as a wedding gift.” This remark sounded offensive to ʿAbbas and his son, and in consequence they decided to slay the Khalif. Osama gives the further account that Ibn Munqidh said to ʿAbbas: “How can you endure the evil reports I hear about your son?” “What are they?” asked ʿAbbas. Osama then interposed: “People say that az-Zafir has commerce with thy son and suspect the Khalif of doing with him what one does with women.” ʿAbbas was aroused and asked indignantly, “But what can I do?” Ibn Munqidh replied, “Assassinate the Khalif, then the dishonour will be purged from thee.” Ibn Khallikan (i. 222), in his life of az-Zafir, states that ʿAbbas said to his son, “You are ruining your reputation by keeping company with az-Zafir; your familiarity with him is the subject of public talk; kill him then, for it is thus that thou wilt vindicate thy honour from these foul suspicions.” When Nasir had made up his mind to the murder he invited the Khalif to visit him in his house in the Armourers’ Market, and there he concealed a band of confederates. On Thursday, the last day of Muharram, 549 (15th April, 1154), the Khalif went privately with a single black slave to Nasir’s house and there the conspirators fell upon him, slew him, and buried his body beneath the floor of the room; according to Osama they slew the black slave at the same time, but this does not seem to have been the case as we find the slave afterwards showing the place where the body was buried. The same night Nasir went to his father and informed him of what he had done.