صحيح البخاري Sahih Bukhari كتاب الأيمان والنذور The Book of Oaths and Vows
بَابُ مَنْ نَذَرَ أَنْ يَصُومَ أَيَّامًا فَوَافَقَ النَّحْرَ أَوِ الْفِطْرَ:

(32) Chapter. If somebody has vowed that he will observe Saum (fast) for a few successive days and then those days appear to coincide with Eid-ul-Adha or Eid-ul-Fitr (should he observe fast then or make expiation, or observe fast on other days)?

2 hadith
Hadith 6705
حَدَّثَنَا مُحَمَّدُ بْنُ أَبِي بَكْرٍ الْمُقَدَّمِيُّ ، حَدَّثَنَا فُضَيْلُ بْنُ سُلَيْمَانَ ، حَدَّثَنَا مُوسَى بْنُ عُقْبَةَ ، حَدَّثَنَا حَكِيمُ بْنُ أَبِي حُرَّةَ الْأَسْلَمِيُّ ، أَنَّهُ سَمِعَ عَبْدَ اللَّهِ بْنَ عُمَرَ رَضِيَ اللَّهُ عَنْهُمَا ، سُئِلَ عَنْ رَجُلٍ نَذَرَ أَنْ لَا يَأْتِيَ عَلَيْهِ يَوْمٌ إِلَّا صَامَ ، فَوَافَقَ يَوْمَ أَضْحًى أَوْ فِطْرٍ ، فَقَالَ : " لَقَدْ كَانَ لَكُمْ فِي رَسُولِ اللَّهِ أُسْوَةٌ حَسَنَةٌ ، لَمْ يَكُنْ يَصُومُ يَوْمَ الْأَضْحَى وَالْفِطْرِ ، وَلَا يَرَى صِيَامَهُمَا " .
Narrated `Abdullah bin `Umar: that he was asked about a man who had vowed that he would fast all the days of his life then the day of `Id al Adha or `Id-al-Fitr came. `Abdullah bin `Umar said: You have indeed a good example in Allah's Apostle. He did not fast on the day of `Id al Adha or the day of `Id-al-Fitr, and we do not intend fasting on these two days.
Hadith Reference Sahih Bukhari / The Book of Oaths and Vows / Hadith: 6705
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة
Hadith 6706
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ ، حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ ، عَنْ يُونُسَ ، عَنْ زِيَادِ بْنِ جُبَيْرٍ ، قَالَ : كُنْتُ مَعَ ابْنِ عُمَرَ ، فَسَأَلَهُ رَجُلٌ ، فَقَالَ : نَذَرْتُ أَنْ أَصُومَ كُلَّ يَوْمِ ثَلَاثَاءَ ، أَوْ أَرْبِعَاءَ مَا عِشْتُ ، فَوَافَقْتُ هَذَا الْيَوْمَ يَوْمَ النَّحْرِ ، فَقَالَ : " أَمَرَ اللَّهُ بِوَفَاءِ النَّذْرِ ، وَنُهِينَا أَنْ نَصُومَ يَوْمَ النَّحْرِ " ، فَأَعَادَ عَلَيْهِ ، فَقَالَ : مِثْلَهُ لَا يَزِيدُ عَلَيْهِ .
Narrated Ziyad bin Jubair: I was with Ibn `Umar when a man asked him, "I have vowed to fast every Tuesday or Wednesday throughout my life and if the day of my fasting coincided with the day of Nahr (the first day of `Id-al- Adha), (What shall I do?)" Ibn `Umar said, "Allah has ordered the vows to be fulfilled, and we are forbidden to fast on the day of Nahr." The man repeated his question and Ibn `Umar repeated his former answer, adding nothing more.
Hadith Reference Sahih Bukhari / The Book of Oaths and Vows / Hadith: 6706
Hadith Grading محدثین: أحاديث صحيح البخاريّ كلّها صحيحة