Shama-il Tirmidhi Chapter 039, Hadith Number 021 (268).

Ibn 'Umar Radiyallahu 'Anhu reports.. "Hafsah (my sister, Ummul Mu-mineen) related to me that when the time of fajr began (subh saadiq), and the mu-adh-dhin called out the adhaan, Rasulullah Sallallahu 'Alayhi Wasallam performed two short rak-'ahs".

Commentary
Regarding the sunnah of fajr, it has been stated in most of the narrations that Sayyidina Rasulullah Sallallahu'Alayhi Wasallam shortened its rak'ahs. To the extent that some 'ulama say, only the Faatiha (Alhamdu) should be recited and it is not necessary to add a surah to it. The fact is, that it has been ascertained that Sayyidina Rasulullah sallallahu'Alayhi Wasallam recited a surah therein. Certainly it is better to recite a short surah. A narration in the Sahih Muslim is mentioned that Sayyidina Rasullullah Sallallahu 'Alayh Wasallam recited the surahs of Kaafirun and AI-Ikhlaas in this sunnah. Other surahs have also been reported in the ahaadith. Sayyidina Rasulullah Sallallahu 'Alayhi Wasallam has said. "How wonderful these two surahs are, that they are recited in the sunnahs of the fajr salaah".

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