Sayyiduna Ibn Abbas (may Allah be pleased with them) narrated that when the Prophet (peace and blessings of Allah be upon him) came to Madinah (in the second year), he saw the Jews fasting on the day of Ashura. He inquired from them about the reason for this. They replied that this is a good day; on this day Allah Almighty saved the Children of Israel from their enemy (Pharaoh), so Musa (peace be upon him) fasted on this day. The Prophet (peace and blessings of Allah be upon him) said, "We are more deserving of following Musa (peace be upon him) than you." Thus, he fasted on that day and ordered his Companions to do so as well.