is calculated solely by the movement (1) of the sun, whereas the Muslims’ fasting follows the lunar month, as do their pilgrimage and all obligatory and recommended observances reckoned by months. The Prophet (peace and blessings be upon him) therefore said: “We have a greater right to Moses than you do.” The implications of this greater right became evident both in honoring this day and in determining its date. They determined its date incorrectly because it shifts within the solar year, just as the Christians incorrectly fixed the time of their fast by placing it in a season of the year in which the lunar months vary.

Section

As for the second difficulty—that Quraysh used to fast ‘Āshūrā’ during the pre-Islamic period, and that the Messenger of Allah (peace and blessings be upon him) also used to fast it—there is no doubt that Quraysh revered this day. They would clothe (2) the Kaaba on it, and fasting on it was part of fully honoring it. However, they reckoned time only by the new moons, so for them it fell on the tenth of Muharram. When the Prophet (peace and blessings be upon him) arrived in Medina (3), he found them honoring that day and fasting on it. He asked them about it, and they said: “It is the day on which Allah saved (4) Moses and his people from Pharaoh.” He said: “We have a greater right to Moses than you do.” He therefore fasted on it and instructed others to fast on it (5), affirming and reinforcing its honored status. He declared that he (peace and blessings be upon him) and his community had a greater right to Moses than the Jews did. Thus, if Moses fasted on it in gratitude to Allah, we have a greater right to follow his example (6) than the Jews do—especially if we hold that the religious law of those before us is also our law, unless our law contradicts it.