Eid al-Ghadir (Arabic: عید الغَدیر) is among important feasts and happy holidays of Shi'a held on Dhu l-Hijja 18; when according to reports, the noble Prophet (s) appointed Ali b. Abi Talib (a) as his caliph and the Imam after himself following an order from God. That event happened in the Prophet's (s) Hajjat al-Wida' (the Farewell Hajj), in 10/632 in a place called Ghadir Khumm.
In Shi'a hadiths, the anniversary has been called "Eid Allah al-Akbar" (the greatest eid of God), Eid of Ahl al-Bayt (a) and "Ashraf al-A'yad" (Most Honorable Eid). Shi'a celebrate this day around the world with various customs.
The Prophet (s) began his journey from Medina toward Mecca for hajj on Dhu l-Qa'da 24 or 25 of 10/632 accompanied with thousands of people. Since that hajj was the last hajj of the Prophet (s), it was later called "Hajjat al-Wida'". When hajj rituals finished and the Prophet (s) left Mecca toward Medina, they arrived at Ghadir Khumm, on Dhu l-Hijja 18 and In this place, Gabriel revealed the verse of Tabligh to the Prophet (s) and delivered him the order of God for appointment of Ali (a) as Wali and Wasi (successor) after the Prophet (s) and announcing it to people.
The Prophet (s) gathered people in Ghadir Khumm, raised Ali's (a) hand so that everyone sees and asked, "O people! Do I not have wilaya (guardianship) over you more than you have over yourself?" People answered, "Yes, O Prophet (s)!" Then, the Prophet (s) said:
- "God is my wali (guardian) and I am wali of the believers; and I have wilaya over them more than they have over themselves. So anyone I am his wali, Ali (a) is his wali."