It is narrated from Umm al-Mu'minin Sayyida Aisha (may Allah be pleased with her), she said: In the days of ignorance, people used to fast on the day of Ashura, and the Messenger of Allah (peace and blessings be upon him) also used to fast on this day during the time of ignorance. Then when the Messenger of Allah (peace and blessings be upon him) came to Madinah, he fasted on this day and ordered the people to fast on this day as well. Then when Ramadan was made obligatory, only the fasts of Ramadan remained obligatory, and the fast of Ashura was abandoned, so whoever wishes may fast on this day and whoever wishes may leave it.

It is narrated from Humaid bin Abdur Rahman bin Awf that he heard from Sayyiduna Muawiyah bin Abi Sufyan, may Allah be pleased with them both, who said, the year he performed Hajj and he was on the pulpit: O people of Madinah! Where are your scholars? I heard the Messenger of Allah, peace and blessings be upon him, say about this day: "This is the day of Ashura, fasting on this day is not obligatory upon you, and I am fasting. So whoever wishes may fast, and whoever wishes may not fast."

Imam Malik (may Allah have mercy on him) was informed that Sayyiduna Umar ibn al-Khattab (may Allah be pleased with him) sent a message to Harith ibn Hisham saying: "Tomorrow is the day of Ashura, so fast and order your family to fast as well."