Mishkat al-Masabih

Abu Huraira reported the Prophet (ﷺ) as saying, “There is no fara’ and no ‘atira.” He said that the fara’ was the first animal born to them which they sacrificed to their idols, and the ‘atira was observed in Rajab.* * These were practices of the idolatrous pre-Islamic Arabs. While the fara' sacrifice was abolished in Islam, it is said that the sacrifice of a sheep or goat in Rajab, known as the ‘atira, was continued in the early days of Islam and then abolished. (Bukhari and Muslim.)