أَخْبَرَنَا ابْنُ صَاعِدٍ ، ثنا عُبَيْدُ اللَّهِ بْنُ سَعْدٍ ، ثنا عَمِّي ، ثنا أبِي ، عَنِ ابْنِ إِسْحَاقَ ، حَدَّثَنِي مَكْحُولٌ بِهَذَا ، وَقَالَ فِيهِ " إِنِّي لأَرَاكُمْ تَقْرَءُونَ خَلْفَ إِمَامِكُمْ إِذَا جَهَرَ " ، قُلْنَا : أَجَلْ ، وَاللَّهِ يَا رَسُولَ اللَّهِ هَذَا ، قَالَ : " لا تَفْعَلُوا إِلا بِ أُمِّ الْقُرْآنِ فَإِنَّهُ لا صَلاةَ لِمَنْ لَمْ يَقْرَأْ بِهَا ".
This same narration is transmitted with some other chains as well, however, in it are these words: "The Noble Prophet (peace be upon him) said: 'I think you people recite behind your Imam when he is reciting aloud.'" We said: "Yes, O Messenger of Allah! By Allah, we recite quickly." The Noble Prophet (peace be upon him) said: "Do not do so, but recite Surah Al-Fatihah, because whoever does not recite it, his prayer is not valid."