In the year of Conquest the Messenger of Allah ﷺ recited a verse at which a prostration should be made and all the people prostrated themselves. Some were mounted, and some were prostrating themselves on the ground, and those who were mounted prostrated themselves on their hands.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَرَأَ عَامَ الْفَتْحِ سَجْدَةً فَسَجَدَ النَّاسُ كُلُّهُمْ مِنْهُمُ الرَّاكِبُ وَالسَّاجِدُ فِي الأَرْضِ حَتَّى إِنَّ الرَّاكِبَ لَيَسْجُدُ عَلَى يَدِهِ  

The Messenger of Allah ﷺ would recite to us a surah (according to the version of Ibn Numair) outside the prayer (the agreed version goes), then he would prostrate along with him, and none of us could find a place for his forehead.  

كَانَ رَسُولُ اللَّهِ ﷺ يَقْرَأُ عَلَيْنَا السُّورَةَ قَالَ ابْنُ نُمَيْرٍ فِي غَيْرِ الصَّلاَةِ ثُمَّ اتَّفَقَا فَيَسْجُدُ وَنَسْجُدُ مَعَهُ حَتَّى لاَ يَجِدُ أَحَدُنَا مَكَانًا لِمَوْضِعِ جَبْهَتِهِ  

The Messenger of Allah ﷺ used to recite the Qur'an to us. When he came upon the verse containing prostration, he would utter the takbir (Allah is most great) and we would prostrate ourselves along with him. The narrator 'Abd al-Razzaq said: Al-Thawri liked this tradition very much. Abu Dawud said: This was liked by him for this contains the uttering of takbir.  

كَانَ رَسُولُ اللَّهِ ﷺ يَقْرَأُ عَلَيْنَا الْقُرْآنَ فَإِذَا مَرَّ بِالسَّجْدَةِ كَبَّرَ وَسَجَدَ وَسَجَدْنَا