Volume 6, Book 61, Number 528:
Narrated Abu Sa’id Al-Mu’alla:
While I was praying, the Prophet called me but I did not respond to his call. Later I said, “O Allah’s
Apostle! I was praying.” He said, “Didn’t Allah say: ‘O you who believe! Give your response to Allah
(by obeying Him) and to His Apostle when he calls you’?” (8.24)
He then said, “Shall I not teach you the most superior Surah in the Qur’an?” He said, ‘(It is),
‘Praise be to Allah, the Lord of the worlds. ‘ (i.e., Surat Al-Fatiha) which consists of seven repeatedly
recited Verses and the Magnificent Qur’an which was given to me.”

Volume 6, Book 60, Number 226:
Narrated Abu Said Al-Mualla:
While I was praying, the Prophet passed by and called me, but I did not go to him till I had fin –
ished my prayer. When I went to him, he said, “What prevented you from coming?” I said, “I was
praying.” He said, “Didn’t Allah say” “O you who believes Give your response to Allah (by obeying
Him) and to His Apostle.” (8.24) Then he added, “Shall I tell you the most superior Sura in the Qur’an
before I go out of the mosque?” When the Prophet intended to go out (of the Mosque), I reminded
him and he said, “That is: “Alhamdu-lillahi Rabbil-‘Alamin (Surat-al-fatiha)’ which is the seven oft
repeated verses (Al-Mathani) and the Grand Quran which has been given to me.”