حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا الْمُغِيرَةُ، - يَعْنِي الْحِزَامِيَّ - عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ إِنَّمَا الإِمَامُ لِيُؤْتَمَّ بِهِ فَلاَ تَخْتَلِفُوا عَلَيْهِ فَإِذَا كَبَّرَ فَكَبِّرُوا وَإِذَا رَكَعَ فَارْكَعُوا وَإِذَا قَالَ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ ‏.‏ فَقُولُوا اللَّهُمَّ رَبَّنَا لَكَ الْحَمْدُ ‏.‏ وَإِذَا سَجَدَ فَاسْجُدُوا وَإِذَا صَلَّى جَالِسًا فَصَلُّوا جُلُوسًا أَجْمَعُونَ ‏"‏ ‏.‏

Abu Huraira reported:The Messenger of Allah (ﷺ) said: The Imam is appointed, so that he should be followed, so don't be at variance with him. Recite takbir when he recites it; bow down when he bows down and when he says:" Allah listens to him who praises Him," say:" O Allah, our Lord, to Thee be the Praise." And when he (the Imam) prostrates, you should also prostrate, and when he says prayer sitting, you should all observe prayer sitting