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Cyril of Jerusalem, or St. Cyril of Jerusalem, was a bishop who presided over the See of Jerusalem in the fourth century AD. (A see is an area of jurisdiction given to an episcopal leader.) Cyril of Jerusalem is known as one of the fathers of the Eastern Catholic Church, many of whom resisted parts of the Nicene Creed, especially the doctrine of homoousion (the teaching that Jesus and God the Father are of the “same substance”). Eventually, however, Cyril came to accept this doctrine and the Nicene orthodoxy. Cyril of Jerusalem attended the Council of Constantinople in 381.
Cyril of Jerusalem was repeatedly persecuted by a fellow churchman named Acacius, who was an Arian. Arianism asserts that, since God “begot” Christ, there was a time when God the Son did not exist. These differing views created a lot of conflict in the early church, most likely because the doctrine of the Trinity is not stated outright in Scripture, but its definition must be inferred from various passages (1 Corinthians 8:6; 2 Corinthians 3:17; Colossians 2:9; Isaiah 9:6; John 10:30; Matthew 1:23). Arianism was eventually declared a heresy at the Council of Nicaea, but, for a long time, both views were accepted as potentially orthodox, and Arianism was the predominate view in many parts of the world. As often happens in situations where differing theologies are trying to coexist in one body, there was some conflict.
Acacius repeatedly attempted to depose Cyril of Jerusalem. Once, during a food shortage in Jerusalem, Cyril took some sacramental items from the church and sold them in order to buy food for the people in his see. Acacius used this incident to discredit Cyril and persisted in attempts to bring Cyril to account for what he had done. He eventually succeeded in running Cyril out of town. However, the next year, an anti-Arian council reinstated Cyril, and Acacius was deposed. A year later, this was reversed, and Cyril was again exiled from Jerusalem. Many times these reversals in fortune were linked to reversals in power at the highest levels. When Emperor Julian succeeded Emperor Constantius, who had banished Cyril of Jerusalem, Cyril was allowed to come back. Unfortunately, Emperor Valens came to power seven years later, and, since Valens was an Arian, Cyril was again sent from his home and his post. Two years after that, when Emperor Gratian came to power, Cyril was again allowed to return home, and he remained there until his death eight years later, in 386.
Not much of the writing of Cyril of Jerusalem is extant. He is perhaps best known for his catechetical lectures, in which Cyril described how to find Jesus’ cross and various holy sites in Jerusalem, instructed priests on the “proper” way to hold the bread of communion, and directed Christians to make the sign of the cross “when we eat and drink, sit, go to bed, get up, talk, walk, in short, in every action” (Catechism iv, 14). Cyril stressed many doctrines that are today accepted as part of Roman Catholicism, including transubstantiation, prayers for the dead, and the idea that the Catholic Church is the “holy Mother of all” (Catechism xviii, 26).