I have derived the permissibility of Mawlid from another source of the Sunna [besides Ibn Hajar's deduction from the hadith of `Ashura'], namely :The hadith found in Bayhaqi, narrated by Anas, that "The Prophet slaughtered a `aqiqa [sacrifice for newborns] for himself after he received the prophecy," although it has been mentioned that his grandfather `Abd al-Muttalib did that on the seventh day after he was born, and the `aqiqa cannot be repeated. Thus the reason for the Prophet's action is to give thanks to Allah for sending him as a mercy to the worlds, and to give honor to his Umma, in the same way that he used to pray on himself. It is recommended for us, therefore, that we also show thanks for his birth by meeting with our brothers, by feeding people, and other such good works and rejoicing." This hadith confirms the aforementioned hadith of the Prophet's emphasis of Monday as the day of his birthday and that of his prophethood. [Husn al-Maqsad fi Amal al-Mawlid Page No. 64-65]