Anas reported:Bilal was commanded (by the Messenger of Allah) to repeat (the phrases of) Adhan twice and once in Iqama. The narrator said: I made a mention of it before Ayyub who said: Except for saying: Qamat-is-Salat [the time for prayer has come]
Anas b. Malik reported:They (the Companions) discussed that they should know the timings of prayer by means of something recognized by all. Some of them said that fire should be lighted or a bell should be rung. But Bilal was ordered to repeat the phrases twice in Adhan, and once in Iqama
This hadith is transmitted by Khalid Hadhdha with the same chain of transmitters (and the words are):When the majority of the people discussed they should know, like the hadith narrated by al-Thaqafi (mentioned above) except for the words:" They (the people) should kindle fire
Abu Mahdhura said that the Messenger of Allah (ﷺ) taught him Adhan like this:Allah is the Greatest, Allah is the Greatest; I testify that there is no god but Allah, I testify that there is no god but Allah; I testify that Muhammad Is the Messenger of Allah, I testify that Muhammad is the Messenger of Allah, and it should be again repeated: I testify that there is no god but Allah, I testify that there is no god but Allah; I testify that Muhammad Is the Messenger of Allah, I testify that Muhammad is the Messenger of Allah. Come to the prayer (twice). Come to success (twice). Ishaq added: Allah is the Greatest, Allah is the Greatest; there Is no god but Allah
Hadis 843 — Sahih Muslim 4:7
حَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا عُبَيْدُ اللَّهِ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ كَانَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم مُؤَذِّنَانِ بِلاَلٌ وَابْنُ أُمِّ مَكْتُومٍ الأَعْمَى .
Ibn Umar reported:The Messenger of Allah (ﷺ) had two Mu'adhdhins, Bilal and 'Abdullah b. Umm Maktum, who (latter) was blind
وَحَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا يَحْيَى، - يَعْنِي ابْنَ سَعِيدٍ - عَنْ حَمَّادِ بْنِ سَلَمَةَ، حَدَّثَنَا ثَابِتٌ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُغِيرُ إِذَا طَلَعَ الْفَجْرُ وَكَانَ يَسْتَمِعُ الأَذَانَ فَإِنْ سَمِعَ أَذَانًا أَمْسَكَ وَإِلاَّ أَغَارَ فَسَمِعَ رَجُلاً يَقُولُ اللَّهُ أَكْبَرُ اللَّهُ أَكْبَرُ . فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " عَلَى الْفِطْرَةِ " . ثُمَّ قَالَ أَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ أَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ . فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " خَرَجْتَ مِنَ النَّارِ " . فَنَظَرُوا فَإِذَا هُوَ رَاعِي مِعْزًى .
Anas b. Malik reported:The Messenger of Allah (ﷺ) used to attack the enemy when it was dawn. He would listen to the Adhan; so if he heard an Adhan, he stopped, otherwise made an attack. Once on hearing a man say: Allah is the Greatest, Allah is the Greatest, the Messenger of Allah (ﷺ) remarked: He is following al-Fitra (al-Islam). Then hearing him say: I testify that there is no god but Allah. there is no god but Allah, the Messenger of Allah (ﷺ) said: You have come out of the Fire (of Hell). They looked at him and found that he was a goat herd