A prominent feature of Islam is that most of its rites and practices were adopted from the pagan Arabian rituals of Muhammad's time. To hide their pagan origins, Muhammad claimed that God initially sanctioned these rites. In fact, before, during, and after his mission, Muhammad continued to perform rites that were nothing more than idolatry. For instance, a hadith of al-Bukhari records that, prior to his calling, Muhammad made sacrifices to the pagan idols:
Narrated 'Abdullah: Allah's Apostle said that he met Zaid bin 'Amr Nufail at a place near Baldah and this had happened before Allah's Apostle received the Divine Inspiration. Allah's Apostle presented a dish of meat(that had been offered to him by the pagans) to Zaid bin 'Amr, but Zaid refused to eat of it and then said (to the pagans), "I do not eat of what you slaughter on your stone altars (Ansabs) nor do I eat except that on which Allah's Name has been mentioned on slaughtering." (Sahih al-Bukhari 7:407)
Despite the fact that the parenthetical statements — "that had been offered to him by the pagans" and "to the pagans" — are not part of the Arabic text, the point is still clear that Muhammad ate food sacrificed to idols while Zaid refused to eat it. This is brought out clearly from the following citations taken from F.E. Peters. According to a tradition reported by Zaid ibn Haritha, who was also present at the event,
The Prophet slaughtered an ewe for one of the idols (nusub min al-ansab); then he roasted it and carried it with him. Then Zayd ibn Amr ibn Nufayl met us in the upper part of the valley; it was one of the hot days of Mecca. When we met we greeted each other with the greeting of the Age of barbarism, in'am sabahan. The Prophet said: "Why do I see you, O son of Amr, hated by your people?" He said, "This (happened) without my being the cause of their hatred; but I found them associating divinities with God and I was reluctant to do the same. I wanted (to worship God according to) the religion of Abraham..." The Prophet said, "Would you like some food?" He said, "Yes." Then the Prophet put before him the (meat of the ewe). He (that is, Zayd ibn Amr) said: "What did you sacrifice to, O Muhammad?""He said, "To one of the idols." Zayd then said: "I am not the one to eat anything slaughtered for a divinity other than God." (Al-Kharqushi, Sharaf al-Mustafa, cited in F. E. Peters, Muhammad and the Religion of Islam[State University of New York Press (SUNY), Albany 1994], pp. 126-127)
Ibn al-Kalbi also confirms that Muhammad offered up an ewe to al-Uzza, "in accordance with the religion of the people." (Ibid., p. 127)
In fact, noted historian of the Arab peoples Philip K. Hitti accepts the veracity of al-Kalbi's report:
Al-'Uzza (the most mighty, Venus, the morning star) had her cult in Nakhlah east of Makkah. According to al-Kalbi, hers was the most venerated idol among the Quraysh, and Muhammad as a young man offered her a sacrifice. (Hitti, History of the Arabs from the Earliest Times to the Present, revised tenth edition, new preface by Walid Khalidi [Palgrave Macmillan, 2002; ISBN: 0-333-63142-0 paperback], p. 99)