The Book of the Adhan (The Call to Prayer)
7/16. Chapter:
The Final Words Of The Adhan
Sunan an-Nasai
أَخْبَرَنَا مُحَمَّدُ بْنُ مَعْدَانَ بْنِ عِيسَى، قَالَ حَدَّثَنَا الْحَسَنُ بْنُ أَعْيَنَ، قَالَ حَدَّثَنَا زُهَيْرٌ، قَالَ حَدَّثَنَا الأَعْمَشُ، عَنْ إِبْرَاهِيمَ، عَنِ الأَسْوَدِ، عَنْ بِلاَلٍ، قَالَ آخِرُ الأَذَانِ اللَّهُ أَكْبَرُ اللَّهُ أَكْبَرُ لاَ إِلَهَ إِلاَّ اللَّهُ .
It was narrated from Al-Aswad that Bilal said: "The final words of the Adhan are: 'Allahu Akbar, Allahu Akbar; La ilaha illallah (Allah is the Greatest, Allah is the Greatest, there is none worthy of worship except Allah.)'"
Reference : Sunan an-Nasa'i 649In-book reference : Book 7, Hadith 24English translation : Vol. 1, Book 7, Hadith 650