حَدَّثَنَا عَبْدُ بْنُ حُمَيْدٍ، أَخْبَرَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لاَ تَقُومُ السَّاعَةُ عَلَى أَحَدٍ يَقُولُ اللَّهُ اللَّهُ " .
It is narrated on the authority of Anas that the Messenger of Allah (PBUH) said: "The Hour (Resurrection) will not occur as long as anyone says: 'Allah, Allah.'" Translation Not Available
Book Ref: Sahih Muslim Book 1 Hadith 274
Web Ref: Sahih Muslim Book 1 Hadith 148 b