Jami` at-Tirmidhi 3227

Narrated Abu Dharr:"I entered the Masjid when the sun had set, and the Prophet (ﷺ) was sitting. He said: 'O Abu Dharr! Do you know where this goes?' I said: 'Allah and His Messenger know better.' He said: 'Indeed it goes to seek permission to prostrate, so it is permitted. And it is as if it has been said to it: "Rise from its setting place.' Then he recited: 'That is its fixed course.'" He said: "That is the recitation of 'Abdullah bin Mas'ud