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ahmad:8621Ḥasan > Ibn Lahīʿah > Abū al-Aswad > ʿAbdullāh b. Rāfiʿ > Abū Hurayrah

[Machine] The Messenger of Allah ﷺ said: "Whoever reaches Ramadan and has missed any part of it, it will not be accepted from them, and whoever fasts voluntarily and has missed any part of Ramadan, it will not be accepted from them until they make up for it."  

أحمد:٨٦٢١حَدَّثَنَا حَسَنٌ حَدَّثَنَا ابْنُ لَهِيعَةَ حَدَّثَنَا أَبُو الْأَسْوَدِ عَنْ عَبْدِ اللهِ بْنِ رَافِعٍ عَنْ أَبِي هُرَيْرَةَ

عَنْ رَسُولِ اللهِ ﷺ قَالَ مَنْ أَدْرَكَ رَمَضَانَوَعَلَيْهِ مِنْ رَمَضَانَ شَيْءٌ لَمْ يَقْضِهِ لَمْ يُتَقَبَّلْ مِنْهُ وَمَنْ صَامَ تَطَوُّعًا وَعَلَيْهِ مِنْ رَمَضَانَ شَيْءٌ لَمْ يَقْضِهِ فَإِنَّهُ لَا يُتَقَبَّلُ مِنْهُ حَتَّى يَصُومَهُ  


See similar narrations below:

Collected by Suyūṭī