The 24th of Zil-Hajj marks the anniversary of the auspicious occasion of Eid-e-Mubahila. This is the day of victory of Muslims over Christians.
The event of Mubahila occurred in the 10th of Hijrah. Najran was a fertile land located in the Northern mountaneous region of Yemen about 20 Kms from Sanaa. About 40,000 Christians inhabited the land divided into 73 small towns. They were idol worshipers historically just like the Arabs but a priest named Femeon, a constructor by profession, preached Christianity in the area of Najran and soon all the population converted to Christianity and Najran became a powerful center of activities of Christians. They also constructed a church and named it \'Kaba-e-Najran\'. They prayed and offered various offerings there which resulted in an annual income of about two hundred thousand Dinars which was used for the priest who lived and studied there.
According to hadith collections, in 631 an Arab Christian envoy from Najran (currently in northern Yemen and partly in Saudi Arabia) came to Muhammad to argue which of the two parties erred in its doctrine concerning Jesus.
After likening Jesus' miraculous birth to Adam's creation, Muhammad called them to mubahala (cursing), where each party should ask God to destroy the lying party and their families. Muhammad, to prove to them that he is a prophet, brought his daughter Fatimah and his surviving grandchildren Hasan ibn Ali and Husayn ibn Ali, and Ali ibn Abi Talib and came back to the Christians but when one of the Christian monks saw their faces, he advised his companions to withdraw from Mubahala for the sake of their lives and families. Thus the Christian monks vanished from the Mubahala place.