Sahih Muslim Hadith 2661

English

[26611 130 – (…) It was narrated that Abü Müsã [may Allah be pleased with them] said: "The people of Iaibar used to fast on the day of 'Ashârâ', and they took it as a festival and dressed their worni in their jewelry and finery on that day. The Messenger of AllahJ said: 'Then you (Muslims) should fast (on that day)."