St. Celestine I was a Roman deacon when elected pope in 422. A major campaign of his pontificate was his vigorous attack on Nestorianism, the unorthodox teaching of Patriarch Nestorius of Constantinople, which stressed that Christ’s human and divine natures were independent and which denounced the Virgin’s title Theotokos (God-bearer).
Celestine also challenged the doctrine of Pelagius, which minimized the role of divine grace in man’s salvation. In 429, Celestine sent the French bishops SS. Germanus of Auxerre and Lupus of Troyes to combat Pelagianism in England.
It was Celestine who sent St. Palladius as the first bishop to Ireland in 431. St. Patrick would be Palladius’ successor.
Also, during his papacy, Celestine assigned Archbishop St. Cyril of Alexandria with Nestorius’ recantation at the Council of Ephesus in 431. Celestine approved the council’s decision to condemn, depose and banish Nestorius, which caused a schism that remained unresolved for more than a century.
Adapted by A.J. Valentini