Hadith

Muhammad ibn al-Hasan said: "Malik ibn Anas informed us from Yazid ibn Ziyad, the mawla of Banu Hasim, that Abdullah ibn Rafi, the mawla of Salaman, the wife of Prophet (Pbuh), asked Abu Hurayrah about the times of the prayer and Abu Hurayrah said, 'I will tell you: pray Zuhr when the length of] your shadow is equal to your height. Asr when your shadow is twice your height, Maghrib when the sun has set, and Isha from then until the [passing of a] third of the night, and, should you sleep until passing of half the night, then let your eyes not sleep, and pray subh in darkness.

Muhammad said: " This was the verdict of Abu Hanifa, may Allah have mercy on him, concerning the name of Asr, and used to consider the time when the [dawn] glowed clearly as Fajr. As for our verdict, we say that when the shadow [of an object] has grown longer than the object, and therefore has arrived and exceeded the length of the object as the sun moves beyond its zenith, the the time of Asr has arrived. As for Abu Hanifah, he said that the time for Asr has arrived. As for Abu Hanifah, he said that the time for Asr does not arrive until the shadow [of an object] become twice its length