The Messenger of Allah ﷺ said: One is not credited with having observed the prayer without the recitation (of al-Fatiha). So said Abu Huraira: (The prayer in which) the Messenger of Allah ﷺ recited in a loud voice, we also recited that loudly for you (and the prayer in which) he recited inwardly we also recited inwardly for you (to give you a practical example of the prayer of the Holy Prophet).  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ صَلاَةَ إِلاَّ بِقِرَاءَةٍ قَالَ أَبُو هُرَيْرَةَ فَمَا أَعْلَنَ رَسُولُ اللَّهِ ﷺ أَعْلَنَّاهُ لَكُمْ وَمَا أَخْفَاهُ أَخْفَيْنَاهُ لَكُمْ  

In every prayer there is a recitation. We make you listen what the Messenger of Allah ﷺ made us listen, and we keep hidden from you what he kept hidden from us. (Using translation from Abū Dāʾūd 797)   

أَبُو هُرَيْرَةَ كُلُّ صَلَاةٍ يُقْرَأُ فِيهَا فَمَا أَسْمَعَنَا رَسُولُ اللهِ ﷺ أَسْمَعْنَاكُمْ وَمَا أَخْفَى عَلَيْنَا أَخْفَيْنَا عَلَيْكُمْ  

[Machine] I heard Abu Hurairah saying, "In every prayer, there is recitation." So we never heard the Messenger of Allah (PBUH) reciting so loudly that you could hear him, nor did he recite so softly that you could not hear him.  

سَمِعْتُ أَبَا هُرَيْرَةَ يَقُولُ «فِي كُلِّ صَلَاةٍ قِرَاءَةٌ» فَمَا أَسْمَعَنَا رَسُولُ اللَّهِ ﷺ أَسْمَعْنَاكُمْ وَمَا أَخْفَى عَلَيْنَا أَخْفَيْنَا عَنْكُمْ