Eid al-Adha (the Festival of the Sacrifice) is celebrated on the 10th-12th of the Islamic month ofDhū al-Ḥijja, at the conclusion of the annual hajj pilgrimage to Mecca.Muslims around the world mark the holiday with the sacrifice of a sheep or other animal—or, as is often the case for the millions of pilgrims who join the hajj annually—with a sacrifice offered in their name.

Like many rituals associated with the hajj, Eid al-Adha is connected to the story of Abraham. The holiday commemorates Abraham’s willingness to sacrifice his son, traditionally understood to be Ishmael, and his sacrifice of a sheep in his place (Quran 37:100-111). Also like other aspects of the hajj, the holiday also continues a pre-Islamic Meccan sacrifice tradition.

Islamic law requires sacrificial animals to be of a certain age and free from blemishes. Those performing the sacrifice recite prayers before and after, including the invocation of God’s name, the bismillah, with which the Quran begins. They also turn the animal towards the Ka῾ba, the sacred black cube that stands at the center of the Grand Mosque in Mecca. One third of the meat of the sacrifice is kept by the individual and his family, and the rest is given away given away to the poor.

In addition to the sacrifice and the special prayers that are recited in the mosque, the holiday is marked by visits and gift-giving to friends and relatives. Known asdīd ō bāz dīd in Persian, the exchange of visits served as the setting (and the title) for a seminal Iranian short story by modern writer Jalal Al-e Ahmad.