Thesis statement:
In clarifying the Incarnation after Nicaea, Gregory of Nazianzus’s defense of Mary as Theotokos also promoted extra-biblical teachings about the mother of Jesus that linger in Christian thought today.
Nicaea’s creed proved insufficient to effectively squash Arian teachings. Between 325 and 381, scholars continued to clarify biblical Christology, declaring that, in his Incarnation, Jesus experienced full humanity and full deity. Gregory of Nanzianzus specifically referenced the Virgin Mary:
“I join in One the Son, who was begotten of the Father, and afterward of the Virgin Mary, and that I do not call Him two Sons, but worship Him as One and the same in undivided Godhead and honour.” (2nd Letter to Cledonius, against Apollonarius)
As bishop of Constantinople and overseer of the council in 381, Gregory argued post-Nicaea that Mary as Theotokos, “a God-bearing virgin” (Oratio 29), was critical evidence supporting Jesus’s deity and humanity.
“If anyone does not believe that Holy Mary is the Mother of God, he is severed from the Godhead. If anyone should assert that He passed through the Virgin as through a channel, and was not at once divinely and humanly formed in her (divinely, because without the intervention of a man; humanly, because in accordance with the laws of gestation), he is in like manner godless.” (To Cledonius the Priest Against Apollinarius. (Ep. CI.) 382 CE)
His robust defense of the Incarnation rested in part on the physical relationship of Jesus to his mother. The revised creed in 381 included “born of the Virgin Mary” to concretely associate Jesus the man with Mary the woman who conceived, carried, and birthed him.
But in including Mary in Christological discussions, Nazianzus also upheld teaching from the apocryphal Protoevangelium of James that Mary was holy, or had been purified spiritually prior to her pregnancy. Gregory watered the seeds of what would grow into a dogma central to her identity—the Immaculate Conception.
“Conceived by the Virgin, Luke 1:35 who first in body and soul was purified by the Holy Ghost (for it was needful both that Childbearing should be honoured, and that Virginity should receive a higher honour)…” (Oratio 38:13, Dec. 25, 380, or Jan. 6, 381).
“That non-bride faithful Mother, the Spirit purified prior, as man, a confined mortal, He came: but He was purified.” (Carmina IX)
As the church’s Christological conclusions developed between Nicaea and Ephesus, so too did its understanding of Mary’s identity. Nazianzus rightly affirmed Mary as Theotokos, but his willingness to depend on extra-biblical material, particularly the Protoevangelium of James, constitutes a mixed legacy that still affects how the church understands the persons of Mary and Jesus.