Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bayhaqi:2391 – Abū ʿAbdullāh al-Ḥāfiẓ And ʾAbū Bakr b. al-Ḥasan al-Qāḍī > Abū al-ʿAbbās Muḥammad b. Yaʿqūb > Muḥammad b. Isḥāq al-Ṣaghānī > Ḥassān b. ʿAbdullāh > al-Mufaḍḍal > Abū Ṣakhr > Muḥammad b. Kaʿb Sabʿ from al-Mathānī

[Machine] "It is the Mother of the book, and it is seven verses, in the name of Allah, the Most Gracious, the Most Merciful."  

البيهقي:٢٣٩١ – وَأَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ وَأَبُو بَكْرِ بْنُ الْحَسَنِ الْقَاضِي قَالَا ثنا أَبُو الْعَبَّاسِ مُحَمَّدُ بْنُ يَعْقُوبَ ثنا مُحَمَّدُ بْنُ إِسْحَاقَ الصَّغَانِيُّ ثنا حَسَّانُ بْنُ عَبْدِ اللهِ ثنا الْمُفَضَّلُ عَنْ أَبِي صَخْرٍ عَنْ مُحَمَّدِ بْنِ كَعْبٍ سَبْعًا مِنَ الْمَثَانِي قَالَ

هِيَ أُمُّ الْكِتَابِ وَهِيَ سَبْعُ آيَاتٍ بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ  

See similar narrations below:

Collected by Qurʾān, Suyūṭī