The Book of Oaths and Vows
35/35. Chapter:
If A Person Dies With A Vow Unfulfilled
Sunan an-Nasai
أَخْبَرَنَا مُحَمَّدُ بْنُ آدَمَ، وَهَارُونُ بْنُ إِسْحَاقَ الْهَمْدَانِيُّ، عَنْ عَبْدَةَ، عَنْ هِشَامٍ، - وَهُوَ ابْنُ عُرْوَةَ - عَنْ بَكْرِ بْنِ وَائِلٍ، عَنِ الزُّهْرِيِّ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَبْدِ اللَّهِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ جَاءَ سَعْدُ بْنُ عُبَادَةَ إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَ إِنَّ أُمِّي مَاتَتْ وَعَلَيْهَا نَذْرٌ فَلَمْ تَقْضِهِ . قَالَ " اقْضِهِ عَنْهَا " .
It was narrated that Ibn 'Abbas said: "Sa'd bin 'Ubadah came to the Prophet and said: 'My mother died and she had sworn a vow, but she did not fulfill it.' He said: 'Fulfill it on her behalf.'"
Reference : Sunan an-Nasa'i 3819In-book reference : Book 35, Hadith 59English translation : Vol. 4, Book 35, Hadith 3850