Muwatta Malik, Book 18, Hadith 7 (USC-MSA)

Yahya related to me from Malik from Abd ar-Rahman ibn Harmala al- Aslami from Said ibn al-Musayyab that the Messenger of Allah, may Allah bless him and grant him peace, said, "People will remain in good as long as they are quick to break the fast."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ حَرْمَلَةَ الأَسْلَمِيِّ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ لاَ يَزَالُ النَّاسُ بِخَيْرٍ مَا عَجَّلُوا الْفِطْرَ ‏" ‏ ‏.‏

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also referenced under: Book 18, Hadith 640 (In-Book)