What did the Prophet Muhammad (saw) say to Adi b. Hatim (Allah be pleased with him) when he described the two strings he kept beneath his pillow for distinguishing night from dawn?
 'Adi b. Hatim (Allah be pleased with him) reported that when (this verse) was revealed:                     " Until the white streak of the dawn becomes distinct from the dark streak" (ii. 187) Adi b. Hatim said: Messenger of Allah, verily I keep underneath my pillow two strings, one white and the other black, by which I distinguish night from dawn. Upon this the Messenger of Allah (may peace be upon him) said: Your pillow seems to be very large. For the word khait implies the blackness of the night and the whiteness of the dawn.