Al-Bukhari reported from `Amrah bint `Abdur-Rahman, who used to stay in the apartment of `A'ishah, the wife of the Prophet , that `A'ishah said, "The Prophet sent a man as the commander of a war expedition and he used to lead his companions in prayer with recitation (of the Qur'an). And he would complete his recitation with the recitation of `Say: He is Allah, One.' So when they returned they mentioned that to the Prophet and he said,

«سَلُوهُ لِأَيِّ شَيْءٍ يَصْنَعُ ذَلِكَ؟»

(Ask him why does he do that.) So they asked him and he said, `Because it is the description of Ar-Rahman and I love to recite it. So the Prophet said,

«أَخْبِرُوهُ أَنَّ اللهَ تَعَالَى يُحِبُّه»

(Inform him that Allah the Most High loves him.)'' This is how Al-Bukhari recorded this Hadith in his Book of Tawhid. Muslim and An-Nasa'i also recorded it. In his Book of Salah, Al-Bukhari recorded that Anas said, "A man from the Ansar used to lead the people in prayer in the Masjid of Quba'. Whenever he began a Surah in the recitation of the prayer that he was leading them, he would start by reciting `Say: He is Allah, One' until he completed the entire Surah. Then he would recite another Surah along with it (after it). And used to do this in every Rak`ah. So his companions spoke to him about this saying; `Verily, you begin the prayer with this Surah. Then you think that it is not sufficient for you unless you recite another Surah as well. So you should either recite it or leave it and recite another Surah instead.' The man replied, `I will not leave it off. If you want me to continue leading you (in prayer), I will do this; and if you all do not like it, I will leave you (i.e., I will stop leading you).' They used to consider him to be of the best of them to lead them in prayer and they did not want anyone else to lead them other than him. So, when the Prophet came they informed him of this information and he said,

«يَا فُلَانُ، مَا يَمْنَعُكَ أَنْ تَفْعَلَ مَا يَأْمُرُكَ بِهِ أَصْحَابُكَ، وَمَا حَمَلَكَ عَلَى لُزُوم هَذِهِ السُّورَةِ فِي كُلِّ رَكْعَةٍ؟»

(O so-and-so! What prevents you from doing what your companions are commanding you to do, and what makes you adhere to the recitation of this Surah in every Rak`ah) The man said, `Verily, I love it.' The Prophet replied,

«حُبُّكَ إِيَّاهَا أَدْخَلَكَ الْجَنَّة»

(Your love of it will cause you to enter Paradise.) This was recorded by Al-Bukhari, with a disconnected chain, but in a manner indicating his approval.