Sunan Abi Dawud Book 2, Hadith 399
I stand up to pray and intend to prolong it; but when I hear the cry of a boy I shorten if for fear that his mother might be distressed.
The prophet (ﷺ) did not distinguish between the two surahs until the words “In the name of Allah, the Compassionate, the merciful” was revealed to him. These are the words of Ibn al-sarh.
Mu’adh b. Jabal used to pray along with the Prophet (ﷺ); then he returned and led us in prayer. Sometimes he (the narrator) said: then he returned and led his people in prayer. One night the Prophet (ﷺ) delayed the prayer. Sometimes he (the narrator) mentioned the word “the night prayer”. Then Mu’adh prayed along with the Prophet (ﷺ), then returned to his people and led them in prayer, and recited Surat al-Baqarah. A man turned aside and prayed alone. The people said to him: Have you become a hypocrite, so and so? He replied: I did not become a hypocrite. He then came to the Prophet (ﷺ) and said (to him): Messenger of Allah, Mu’adh prays along with you and then returns and leads us in prayers. We look after camels used for watering and work for by day. He came to us leading us in prayer, and he recited Surah al-Baqarah (in prayer). He (the Prophet) said: Mu’adh, are you a trouble maker? Recite such and such ; recite such and such (surahs) The narrator Abu al-Zubair said (recite) “Glorify the name of the most high lord” (surah lxxxvii) and “By the night when it covers over” (surah xcii). We mentioned this to ‘Amr. He said I think he mentioned it (the names of some surahs).