Adelphopoiesis, or adelphopoiia is a ceremony practiced historically in Orthodox-Christian tradition to unite together two people of the same sex in a church-recognized relationship analogous to siblinghood.
The Christian martyrs Saint Sergius and Saint Bacchus, noted for their friendship in Christ, were cited in church adelphopoiesis ceremonies.
Sergius and Bacchus were fourth-century Syrian Christian soldiers revered as martyrs and military saints by the Catholic, Eastern Orthodox and Oriental Orthodox Churches. Their feast day is 7 October.
Detail of a 7th-century icon of Saints Sergius and Bacchus
Martyrs Saints Sergius and Bacchus
Basilica of Saint Sergius, Rasafa, Syria
Assyrian Church of the East of Mar Sarkis (Saint Sergius), Tehran