Sunan an-Nasa'i, Book 10, Hadith 54 (In-Book) ⓘ

It was narrated that Hittan bin 'Abdullah said: "Abu Musa led us in prayer and when he was sitting, a man from among the people entered and said: 'Prayer is based on righteousness and is always mentioned alongside Zakah (in the Qur'an).' When Abu Musa had said the Salam, he turned to the people and said: 'Which of you spoke these words?' The people kept quiet. Then he said: 'O Hittan, perhaps you said it?' He said: 'No, but I was afraid that you would rebuke me for it.' He said: 'The Messenger of Allah taught us our prayer and Sunnah prayers, and he said: The Imam is appointed to be followed, so when he says the Takbir, say the Takbir; when he says "Not (the way) of those who earned Your Anger, nor of those who went astray," say Amin, and Allah will respond to you; when he rises up from bowing and says, 'Sami' Allalhu liman hamidah (Allah hears those who praise Him), say 'Rabbana lakal-hamd (Our Lord, to You be praise),' and Allah will hear you; when he prostrates, prostrate, and when he sits up, sit up. The Imam should prostrate before you do and sit up before you do.' The Messenger of Allah said: 'This makes up for that.'"

أَخْبَرَنَا مُؤَمَّلُ بْنُ هِشَامٍ، قَالَ حَدَّثَنَا إِسْمَاعِيلُ ابْنُ عُلَيَّةَ، عَنْ سَعِيدٍ، عَنْ قَتَادَةَ، عَنْ يُونُسَ بْنِ جُبَيْرٍ، عَنْ حِطَّانَ بْنِ عَبْدِ اللَّهِ، قَالَ صَلَّى بِنَا أَبُو مُوسَى فَلَمَّا كَانَ فِي الْقَعْدَةِ دَخَلَ رَجُلٌ مِنَ الْقَوْمِ فَقَالَ أُقِرَّتِ الصَّلاَةُ بِالْبِرِّ وَالزَّكَاةِ ‏.‏ فَلَمَّا سَلَّمَ أَبُو مُوسَى أَقْبَلَ عَلَى الْقَوْمِ فَقَالَ أَيُّكُمُ الْقَائِلُ هَذِهِ الْكَلِمَةَ فَأَرَمَّ الْقَوْمُ ‏.‏ قَالَ يَا حِطَّانُ لَعَلَّكَ قُلْتَهَا قَالَ لاَ وَقَدْ خَشِيتُ أَنْ تَبْكَعَنِي بِهَا فَقَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يُعَلِّمُنَا صَلاَتَنَا وَسُنَّتَنَا فَقَالَ ‏"‏ إِنَّمَا الإِمَامُ لِيُؤْتَمَّ بِهِ فَإِذَا كَبَّرَ فَكَبِّرُوا وَإِذَا قَالَ ‏{‏ غَيْرِ الْمَغْضُوبِ عَلَيْهِمْ وَلاَ الضَّالِّينَ ‏}‏ فَقُولُوا آمِينَ يُجِبْكُمُ اللَّهُ وَإِذَا رَكَعَ فَارْكَعُوا وَإِذَا رَفَعَ فَقَالَ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ فَقُولُوا رَبَّنَا لَكَ الْحَمْدُ يَسْمَعِ اللَّهُ لَكُمْ وَإِذَا سَجَدَ فَاسْجُدُوا وَإِذَا رَفَعَ فَارْفَعُوا فَإِنَّ الإِمَامَ يَسْجُدُ قَبْلَكُمْ وَيَرْفَعُ قَبْلَكُمْ ‏"‏ ‏.‏ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ فَتِلْكَ بِتِلْكَ ‏"‏ ‏.‏