When and where
431 in Ephesus
Crisis or controversy
teaching that Mary was not the mother of God;
Proponents of Nestorius began claiming
that Christ was actually
two separate persons, human and divine.
and the following notables:
Convened: Theodosius II, Emperor;
St. Cyril of Alexandria;
St. John Chrysostom;
Ratified: Celestinus I, Pope.
Decrees and resolutions
Decreed that Mary was also Theotokos, mother of God;
Declared that Christ is true God and true man, that he has two
natures (human and divine) joined in one