Non-Catholics (and probably even a few Catholics) commonly confuse the idea of the “Virgin Birth” with the notion of the “Immaculate Conception.” However, the two are quite distinct. While the doctrine of the Virgin Birth teaches that Jesus was born of a virgin mother and, thus, was without an earthly father, the Immaculate Conception refers to the earthly origin of Mary herself.
The doctrine was first officially stated by Pope Pius IX on Dec. 8, 1854. “We declare, pronounce and define,” he wrote, in an encyclical titled “Ineffabilis Deus” (“Ineffable God”), “that the most blessed Virgin Mary, at the first instant of her conception, was preserved immaculate from all stain of original sin, by the singular grace and privilege of the omnipotent God, in virtue of the merits of Jesus Christ, the saviour of mankind, and that this doctrine was revealed by God and therefore must be believed firmly and constantly by all the faithful.”
Believers in the Immaculate Conception have found support for it in Genesis 3:15 and Luke 1:28. Clearly, though, it grows primarily out of subsequent Christian tradition rather than out of the biblical data. Already St. Justin Martyr (d. ca. A.D. 165 ) and St. Irenaeus (d. ca. 200) were calling Mary the “new Eve,” as a parallel to Paul’s biblical description of Jesus as the “new Adam.” By the eighth century, in the Christian East, St. Andrew of Crete (d. 740) and St. John of Damascus (d. ca. 749) were praising Mary’s perfect sinlessness.
