Regarding the first Athaan of Fajr, when should it be given, i.e., how long before the arrival of Fajr?

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The scholars differed in opinion with regard to the first Fajr Athaan. The Shaafi'ee and Hanbali schools are of the view that its time is the second (last) part of the night. Nonetheless, the Maaliki school is of the view that it is in the sixth last part of the night. The evidence that the second view is the most correct is the narration reported by Ibn 'Umar which reads: "The Prophet had two persons who called the Athaan, Bilaal and Ibn Umm Maktoom . He said: "Eat and drink until Ibn Umm Maktoom calls for the Athaan." He [Ibn 'Umar] said: "The difference between the two is very short, as long as it would take one to descend, and the other one to ascend." [Muslim] This is evidence that the first Athaan is close to the time of the beginning of the real time of Fajr. Ibn Hajar said: 'This is evidence for those who are of the opinion that the time of the first Athaan is the time of Suhoor [the predawn meal]." The other evidence is the narration reported by Ibn Mas'ood that the Prophet said: "The Athaan given by Bilaal should not prevent you from having your Suhoor, as he calls when it is still night so that a person who is performing night prayer would end his prayer, and so that the sleeping people would wake up." [Al-Bukhari and Muslim] So, Bilaal used to call Athaan by Suhoor time.

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