Sayyiduna Malik bin al-Huwayrith (may Allah be pleased with him) said: We came to the Messenger of Allah (peace and blessings be upon him), all of us young men of similar age. We stayed with him (peace and blessings be upon him) for twenty nights. The Messenger of Allah (peace and blessings be upon him) was most merciful and gentle. He (peace and blessings be upon him) sensed that we were missing our families, so he (peace and blessings be upon him) asked us about those we had left behind (at home). We told him (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Go back to your families, stay with them, teach them (the religion), and command them (to do good); and when the time of prayer comes, let one of you give the adhan, and let the eldest of you lead you in prayer."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4928