Uqba bin Amir reported,
I heard the Messenger of Allah ﷺ say, "Your Lord marvels at a shepherd of sheep on the peak of a mountain crag who calls the adhan for prayer and then prays. Allah 
says, 'Look at this servant of Mine, calling the adhan and establishing the prayer, fearing Me. I have forgiven My servant and admitted him into Paradise.'"
Azami 1886
Sahihعن عقبة بن عامر قال
سمعت رسول الله ﷺ يقول: يعجب ربكم من راعي غنم في رأس شظية بجبل يؤذن بالصلاة ويصلي، فيقول الله عز وجل: انظروا إلى عبدي هذا يؤذن ويقيم الصلاة، يخاف مني، قد غفرت لعبدي، وأدخلته الجنة.
Abu Dawud (1203) and Nasai (666) both narrated it through the route of Ibn Wahb, from Amr bin Harith, that Abu Ushana Al-Maafiri told him, from Uqba bin Amir, and he mentioned the hadith. Imam Ahmad (17443) also narrated it through this same route. Its chain is sahih. Ibn Hibban also graded it sahih, recording it in his Sahih (1660) through this same route.Abu Ushana, with a dammah on the unpointed letter and a doubled pointed letter, his name was Hayy bin Yuman. He is well known by his kunya, and he is trustworthy. Ahmad, Abu Dawud, and others declared him trustworthy.As for his statement "ash-shaziyyah," it refers to a raised piece at the top of a mountain. It has also been said that it is the huge rock jutting out from the mountain, as if it were the mountain's nose.