Sahih Bukhari Volume 9, Book 95, Hadith 7248

حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا عَبْدُ الْوَهَّابِ، حَدَّثَنَا أَيُّوبُ، عَنْ أَبِي قِلاَبَةَ، حَدَّثَنَا مَالِكٌ، قَالَ أَتَيْنَا النَّبِيَّ صلى الله عليه وسلم وَنَحْنُ شَبَبَةٌ مُتَقَارِبُونَ، فَأَقَمْنَا عِنْدَهُ عِشْرِينَ لَيْلَةً، وَكَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم رَفِيقًا، فَلَمَّا ظَنَّ أَنَّا قَدِ اشْتَهَيْنَا أَهْلَنَا أَوْ قَدِ اشْتَقْنَا سَأَلَنَا عَمَّنْ تَرَكْنَا بَعْدَنَا فَأَخْبَرْنَاهُ قَالَ ‏"‏ ارْجِعُوا إِلَى أَهْلِيكُمْ، فَأَقِيمُوا فِيهِمْ، وَعَلِّمُوهُمْ، وَمُرُوهُمْ ـ وَذَكَرَ أَشْيَاءَ أَحْفَظُهَا أَوْ لاَ أَحْفَظُهَا ـ وَصَلُّوا كَمَا رَأَيْتُمُونِي أُصَلِّي، فَإِذَا حَضَرَتِ الصَّلاَةُ فَلْيُؤَذِّنْ لَكُمْ أَحَدُكُمْ، وَلْيَؤُمَّكُمْ أَكْبَرُكُمْ ‏"‏‏

Narrated By Malik : We came to the Prophet and we were young men nearly of equal ages and we stayed with him for twenty nights. Allah's Apostle was a very kind man and when he realized our longing for our families, he asked us about those whom we had left behind. When we informed him, he said, "Go back to your families and stay with them and teach them (religion) and order them (to do good deeds). The Prophet mentioned things some of which I remembered and some I did not. Then he said, "Pray as you have seen me praying, and when it is the time of prayer, one of you should pronounce the call (Adhan) for the prayer and the eldest of you should lead the prayer."