Sahih Ibn Khuzaymah

Even if a person is alone, whether there is a group of people with him or not, nor is there any other person—contrary to the statement of the one who was asked about giving the adhan during travel and he replied: “For whom will the adhan be given?” He was under the misconception that the adhan is only given to gather people for congregational prayer. Although the general purpose of the adhan is indeed to gather people for congregational prayer, sometimes the adhan is also given to attain its virtue and reward. Do you not see that the Noble Prophet ﷺ commanded Malik bin Huwairith (may Allah be pleased with him) and his cousin that when both of them are on a journey, they should give the adhan and the iqamah, and the elder among them should lead the prayer, even though there was no congregation with them to gather for their adhan and iqamah? Imam Abu Bakr (may Allah have mercy on him) says: In the hadith of Abu Sa‘id (may Allah be pleased with him), it is stated: “When you are in the wilderness, call the adhan in a loud voice, for I heard the Messenger of Allah ﷺ say: ‘Whatever tree, clod, stone, jinn, or human hears his voice will bear witness for him.’” Therefore, to attain the virtue and reward of the adhan, if the mu’adhdhin gives the adhan in the wilderness, even if he is alone, it is better, more excellent, and superior than praying without adhan and takbir. Similarly, the Noble Prophet ﷺ has stated that the sins of the mu’adhdhin are forgiven up to the extent his voice reaches, and every dry and wet thing will bear witness for him. Thus, the one who gives the adhan in the wilderness and during travel will attain this virtue because of giving the adhan for prayer, even if there is no one with him to pray. Because the Noble Prophet ﷺ did not specify this virtue only for the mu’adhdhin who gives the adhan to gather people for congregational prayer (rather, this virtue is attained by every mu’adhdhin).