4-145 Ali ibn Ahmad ibn Musa - may God be pleased with him - narrated that Muhammad ibn Aba Abdullah al-Kufy quoted Al-Hussein ibn Ubaydullah al-Ash’ari, on the authority of Muhammad ibn Isa ibn Ubayd, on the authority of Al-Qasim ibn Yahya, on the authority of his grandfather Al-Hassan ibn Rashid, on the authority of Al-Mufaz’zal ibn Umar, “I asked Aba Abdullah as-Sadiq (MGB), ‘How many festive days do the Muslims have?’ He (MGB) replied, ‘Four.’ I said, ‘I know about the two Eids (Festivals) and Fridays.’ The Imam (MGB) said, ‘Even nobler and greater than them is the eighteenth day of Dhul-Hijja. That was the day on which God’s Prophet (MGB) raised Ali (MGB) up and appointed him as the Master of the people.’ I asked, ‘What should we do on that day?’ The Imam (MGB) replied, ‘It is incumbent upon you to fast in gratitude and recite glorifications for God, even though God deserves to be thanked all the time. The Prophets (MGB) appointed their Trustees in the same manner. You should fast on the day on which the Trustee was appointed and consider it as a day of festivity. For whoever fasts on that day, it would be considered to be more rewarding than doing good deeds for sixty years.’
