(19) باب صَوْمِ يَوْمِ عَاشُورَاءَ
'A'isha (Allah be pleased with her) reported. In the pre-Islamic days fast was observed on the day of Ashura, but with the advent of Islam (its position was ascertained as that of a voluntary fast). Then he who wished to fast fasted, and he who liked to abandon it abandoned it. (DE)
Reference (DE): Sahih Muslim 1125 c (DE)
In-book reference (DE): Book 13, Hadith 145 (DE)
USC-MSA web (English) reference(deprecated numbering scheme): Book 6, Hadith 2501 (DE)