FASTING TASUA' and ashuraa':
Tasu'a and Ashuraa' are respectively the ninth and the tenth of the month of moharram.
Ibn Abass reported:"the prophet may the blessing and peace of Allah be up on him come to madina and found the jews fasting the day of ashuraa'.He asked them:"why are you fasting this day?they said:"this is agreat day.ALLAH saved mossa (Moses)and the tribes of israel from their enemies on this day and therfore moosa fasted on it."the prophet said:"we have more of aright to moosa than you."So he fasted on that day also and ordered the poeple to fast on that day."(al bukhari and muslim)
The prophet may the blessing and peace of Allah be up on him said:"when the following year comes,ALLAH willing,we shall fast both the ninth and the tenth day of muharram(that is to be different from the jews and the christians.)"the prophet,salla Allaho 3alaihi wasalam,died the following year."(Muslim).