صحيح البخاري Sahih Bukhari كتاب الأيمان والنذور The Book of Oaths and Vows
بَابُ مَنْ مَاتَ وَعَلَيْهِ نَذْرٌ:

(30) Chapter. If somebody dies without fulfiling a vow (may somebody else fulfil it on his behalf)?

2 hadith
Hadith 6698
حَدَّثَنَا أَبُو الْيَمَانِ ، أَخْبَرَنَا شُعَيْبٌ ، عَنْ الزُّهْرِيِّ ، قَالَ : أَخْبَرَنِي عُبَيْدُ اللَّهِ بْنُ عَبْدِ اللَّهِ بْنِ عُتْبَةَ ، أَنَّ عَبْدَ اللَّهِ بْنَ عَبَّاسٍ ، أَخْبَرَهُ : " أَنَّ سَعْدَ بْنَ عُبَادَةَ الْأَنْصَارِيّ ، اسْتَفْتَى النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فِي نَذْرٍ كَانَ عَلَى أُمِّهِ ، فَتُوُفِّيَتْ قَبْلَ أَنْ تَقْضِيَهُ ، فَأَفْتَاهُ أَنْ يَقْضِيَهُ عَنْهَا " ، فَكَانَتْ سُنَّةً بَعْدُ .
Narrated Sa`id bin 'Ubada Al-Ansari: that he consulted the Prophet about a vow that had been made by his mother who died without fulfilling it. The Prophet gave his verdict that he should fulfill it on her behalf. The verdict became Sunna (i.e. the Prophet's tradition).
Hadith Reference Sahih Bukhari / The Book of Oaths and Vows / Hadith: 6698
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة
Hadith 6699
حَدَّثَنَا آدَمُ ، حَدَّثَنَا شُعْبَةُ ، عَنْ أَبِي بِشْرٍ ، قَالَ : سَمِعْتُ سَعِيدَ بْنَ جُبَيْرٍ ، عَنْ ابْنِ عَبَّاسٍ رَضِيَ اللَّهُ عَنْهُمَا ، قَالَ : أَتَى رَجُلٌ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، فَقَالَ لَهُ : إِنَّ أُخْتِي قَدْ نَذَرَتْ أَنْ تَحُجَّ وَإِنَّهَا مَاتَتْ ، فَقَالَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : " لَوْ كَانَ عَلَيْهَا دَيْنٌ أَكُنْتَ قَاضِيَهُ ؟ " ، قَالَ : نَعَمْ ، قَالَ : " فَاقْضِ اللَّهَ ، فَهُوَ أَحَقُّ بِالْقَضَاءِ " .
Narrated Ibn `Abbas: A man came to the Prophet and said to him, "My sister vowed to perform the Hajj, but she died (before fulfilling it)." The Prophet said, "Would you not have paid her debts if she had any?" The man said, "Yes." The Prophet said, "So pay Allah's Rights, as He is more entitled to receive His rights."
Hadith Reference Sahih Bukhari / The Book of Oaths and Vows / Hadith: 6699
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة