Sunan al-Shafi'i

It is narrated from Abdur Rahman bin Abi Sa’sa’ah (who was under the care of Sayyiduna Abu Sa’id Khudri, may Allah be pleased with him) that he was sleeping in his lap. He says, Abu Sa’id (may Allah be pleased with him) said to me: “O son! When you are in this wilderness, call the adhan in a loud voice, because I heard the Messenger of Allah ﷺ say: ‘Whoever—human, jinn, stone, or tree—hears the adhan, will bear witness for the mu’adhdhin on the Day of Resurrection.’”