Imam Bukhari narrates: Abdullah bin Yusuf narrated to us, he said: Imam Malik informed us from Abdur Rahman bin Abdullah bin Abdur Rahman bin Abi Sa'sa'ah al-Ansari, then al-Mazini, from his own father, that Abu Sa'id al-Khudri, may Allāh be pleased with him, said to him:

I see that you love sheep and the wilderness. So when you are among your sheep or in your wilderness, and you give the Adhan for your prayer, then raise your voice in giving the Adhan, because to the extent of the mu'adhdhin's voice, whoever hears the Adhan, whether jinn, human, or anything else, it will bear witness for him on the Day of Judgement.

Abu Sa'id said: I have heard this from the Messenger of Allāh ﷺ.