For 10 points, identify this religious practice observed during the daylight hours of Ramadan and also during Yom Kippur.
According to the Twelver Shi'ah, those who travel more than 40 miles in a day are exempt from this practice. In Islam it is called sawm and is ended by the Eid al-Fitr. The Eastern Orthodox dedicates four seasons of it, one of which is during the Holy Week. Jewish traditions dictate that it be practiced to lament the assassination of the governor of Judah, Gedalia. Moses performed this action before receiving the tablets on a mountain from God. For 10 points, identify this religious practice observed during the daylight hours of Ramadan and also during Yom Kippur.
According to the Twelver Shi'ah, those who travel more than 40 miles in a day are exempt from this practice.
fasting [accept obvious equivalents]