(67) باب الصَّوْمِ يَوْمَ النَّحْرِ
Narrated Ziyad bin Jubair:
A man went to Ibn `Umar I. 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
In-book reference: Book 30, Hadith 100
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 31, Hadith 214