(30) باب كَيْفَ الْفَجْرُ
It was narrated from Ibn Mas'ud that the Prophet said:
"Bilal calls the Adhan at night to awaken those of you who are asleep, and so that those who are praying Qiyam cam return. Dawn is not when the light appears like this" - and he gestured with his hand - "rather dawn is when it appears like this: - and he gestured with his two forefingers. '
Reference: Sunan an-Nasa'i 2170
In-book reference: Book 22, Hadith 81
English translation: Vol. 3, Book 22, Hadith 2172