Musnad Ahmad 482:22

Qutaybah ibn Sa'id narrated to us, he said: Ibn Lahi'ah narrated to us, from Abu 'Ashanah, from 'Uqbah ibn 'Amir, that the Prophet, peace and blessings of Allah be upon him, said: "Your Lord marvels at a shepherd of sheep on a mountain peak who calls the Adhan for prayer and performs the Iqamah." "Allah says: 'Look at this servant of Mine, he calls the Adhan and performs the Iqamah for prayer, fearing Me. I have forgiven My servant and admitted him into Paradise.'"