The Novatian Schism was a schism within the Church of Rome in the third century that originated in the differing positions regarding the policy concerning the proper treatment that the church should accord to Christians who had lapsed, that is denied their faith, during times of persecution.
During the Decian persecutions of the mid third century, a debate arose over the proper treatment that the church should accord to Christians who had denied their faith during the persecutions. Following the martyrdom of Bishop Fabian in January 250, an election could not held for his successor until spring of 251 because the church was in such dire straits. At the 251 council a majority vote was cast for Cornelius, who favored acceptance of those who had lapsed under terrible duress. The election of Cornelius, as Bishop of Rome, was repudiated by the clergy who had been most firm against the lapsed during the persecution and, in opposition, they consecrated Novatian Bishop of Rome. Novatian was a Roman presbyter who was known for his orthodox theological work, On the Trinity. Thus, the Church of Rome was faced with two rival bishops, each seeking support of the wider church.
Novatian's party maintained that only God could grant forgiveness for such grievous sin. The Cornelius party argued for a judicious use of "the power of the keys" in forgiving the lapsed after a period of penance. Bishop Cyprian of Carthage became the major proponent for clemency, siding with Bp. Cornelius.
As the arguments mounted, the demarcation between to two sides became more pronounced. Cyprian maintained that salvation was impossible outside the communion of the church and that true penitents must be received back into the fold as expeditiously as possible. Novatian and his supporters held that the church must be preserved in its purity without the defilement of those who had not proved steadfast and even went so far as to deny forgiveness for any serious offense after baptism, such as fornication or idolatry, though pardon might be offered to those deemed near death.
Ultimately, Novatian and his followers were excommunicated by a synod of Roman bishops. With their emphasis on purity and rigorism, the Novatian movement drew significant support throughout the church at large and had a strong following in Phrygia, especially among the Montanists. A Novatian Church lasted for several centuries and was received as a schismatic orthodox group by the Council of Nicea where their affirmation of Christ as being of one substance with the Father was applauded. Later, the sect fell under imperial disfavor. It was forbidden the right of public worship, and its books were destroyed. Most of its members rejoined the mainstream of the Orthodox Church, although the Novatianists were an identifiable group until the seventh century.