Sahih al-Bukhari 1994

Arabic

حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا مُعَاذٌ، أَخْبَرَنَا ابْنُ عَوْنٍ، عَنْ زِيَادِ بْنِ جُبَيْرٍ، قَالَ جَاءَ رَجُلٌ إِلَى ابْنِ عُمَرَ ـ رضى الله عنهما ـ فَقَالَ رَجُلٌ نَذَرَ أَنْ يَصُومَ يَوْمًا، قَالَ أَظُنُّهُ قَالَ الاِثْنَيْنِ، فَوَافَقَ يَوْمَ عِيدٍ‏.‏ فَقَالَ ابْنُ عُمَرَ أَمَرَ اللَّهُ بِوَفَاءِ النَّذْرِ، وَنَهَى النَّبِيُّ صلى الله عليه وسلم عَنْ صَوْمِ هَذَا الْيَوْمِ‏.‏

English translation

Narrated Ziyad bin Jubair:A man went to Ibn `Umar and said, "A man vowed to fast one day (the sub-narrator thinks that he said that the day was Monday), and that day happened to be `Id day." Ibn `Umar said, "Allah orders vows to be fulfilled and the Prophet (ﷺ) forbade the fasting on this day (i.e. Id)

Reference: Sahih al-Bukhari 1994, Book of Fasting. English translation by Dr. Muhammad Muhsin Khan.