عَنْ عَائِشَةَ أَنَّ النَّبِيَّ صلى الله عليه وسلم بَعَثَ رَجُلاً عَلَى سَرِيَّةٍ، وَكَانَ يَقْرَأُ لأَصْحَابِهِ فِي صَلاَتِهِ فَيَخْتِمُ بِ ـ {قُلْ هُوَ اللَّهُ أَحَدٌ} فَلَمَّا رَجَعُوا ذَكَرُوا ذَلِكَ لِلنَّبِيِّ صلى الله عليه وسلم فَقَالَ: سَلُوهُ لأَىِّ شَىْءٍ يَصْنَعُ ذَلِكَ. فَسَأَلُوهُ فَقَالَ لأَنَّهَا صِفَةُ الرَّحْمَنِ، وَأَنَا أُحِبُّ أَنْ أَقْرَأَ بِهَا. فَقَالَ النَّبِيُّ صلى الله عليه وسلم: أَخْبِرُوهُ أَنَّ اللَّهَ يُحِبُّهُ.
Hazrat Aishara narrated:“The Prophetsa dispatched a man as commander of a detachment. In the prayers he led for his companions, he would conclude his recitation with ‘Qul Huwallahu Ahad…’ [i.e., Surah al-Ikhlas] When they returned, they mentioned this to the Prophetsa. He said, ‘Ask him why he does that.’ They asked him, and he replied, ‘Because it describes the Most Merciful, and I love to recite it.’ The Prophetsa said, ‘Tell him that Allah loves him.’”
(Sahih al-Bukhari, Kitab at-tawhid, Bab ma ja’a fi du‘a’i n-nabiyyisa ummatahu ila tawhidillahi tabaraka wa ta‘ala, Hadith 7375)