Hadith 3855
حَدَّثَنَا أَبُو بَكْرٍ، حَدَّثَنَا عِيسَى بْنُ يُونُسَ، عَنْ عُبَيْدِ اللَّهِ بْنِ أَبِي زِيَادٍ، عَنْ شَهْرِ بْنِ حَوْشَبٍ، عَنْ أَسْمَاءَ بِنْتِ يَزِيدَ، قَالَتْ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " اسْمُ اللَّهِ الأَعْظَمُ فِي هَاتَيْنِ الآيَتَيْنِ {وَإِلَهُكُمْ إِلَهٌ وَاحِدٌ لاَ إِلَهَ إِلاَّ هُوَ الرَّحْمَنُ الرَّحِيمُ} وَفَاتِحَةِ سُورَةِ آلِ عِمْرَانَ " .
It was narrated from Asma' bint Yazid that :
the Messenger of Allah (saas) said: "The Greatest Name of Allah is in these two Verses: And your Ilah (God) is One Ilah (God - Allah), La Ilaha Illa Huwa (none has the right to be worshipped but He), the Most Gracious, the Most Merciful.' And at the beginning of Surah Al 'Imran."
Reference : Sunan Ibn Majah 3855
In-book reference : Book 34, Hadith 29