NASAI-KUBRA 2876: from Abū Ayyūb —
[Machine] The Messenger of Allah ﷺ said, "Whoever fasts during the month of Ramadan and follows it with six days of Shawwal, it is as if he has fasted for the entire year."

الكبرى للنسائي ٢٨٧٦: عن ابو ايوب —
قَالَ رَسُولُ اللهِ ﷺ «مَنْ صَامَ رَمَضَانَ وَأَتْبَعَهُ سِتًّا مِنْ شَوَّالٍ فَكَأَنَّمَا صَامَ الدَّهْرَ كُلَّهُ»


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Nasāʾī's Kubrá > Fasting > § [Machine] Mentioning the disagreement of the carriers...
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