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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:19818 – Abū ʿAbdullāh al-Ḥāfiẓ And ʾAbū Saʿīd b. Abū ʿAmr > Abū al-ʿAbbās al-Aṣam > al-Rabīʿ b. Sulaymān

[Machine] Imam Shafi'i, may Allah have mercy on him, said: "Whoever swears by Allah or by one of the names of Allah and then breaks his oath, then he must make expiation."  

البيهقي:١٩٨١٨ – أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ وَأَبُو سَعِيدِ بْنُ أَبِي عَمْرٍو قَالَا ثنا أَبُو الْعَبَّاسِ الْأَصَمُّ أنبأ الرَّبِيعُ بْنُ سُلَيْمَانَ قَالَ

قَالَ الشَّافِعِيُّ رَحِمَهُ اللهُ مَنْ حَلَفَ بِاللهِ أَوْ بِاسْمٍ مِنْ أَسْمَاءِ اللهِ فَحَنِثَ فَعَلَيْهِ الْكَفَّارَةُ