Feast of the Immaculate Conception

The Immaculate Conception is the Catholic doctrine that Mary was conceived without original sin, preserved from the first instant of her existence by a singular grace in view of the merits of Christ. The confusion the feast most often meets is with the virginal conception of Jesus: the Immaculate Conception concerns Mary's own conception by her parents, traditionally named Joachim and Anne, not the conception of her son. Its date, 8 December, sits nine months before the feast of Mary's nativity on 8 September.

The belief was long contested in the medieval West. Thomas Aquinas and others hesitated, holding that it seemed to exempt Mary from the universal need of redemption; the objection was met by the Scotist solution, associated with Duns Scotus, that Mary was redeemed more perfectly, by preservation rather than rescue. Pope Pius IX defined the doctrine as dogma in 1854 in the bull Ineffabilis Deus. The Eastern churches keep a related feast of the Conception of the Theotokos (9 December) without the specific Western definition. It is a holy day of obligation across much of the Catholic world and the patronal feast of several nations.

Four years after Pope Pius IX defined the Immaculate Conception as dogma in 1854, a French peasant girl named Bernadette Soubirous reported that a figure appearing to her at Lourdes identified herself, when pressed repeatedly for a name, by saying in the local dialect words rendered in French as I am the Immaculate Conception, a phrase Bernadette, who had not been taught the theological term, reportedly repeated to her parish priest without understanding what it meant, and Catholic sources treat her use of the exact newly defined phrase as significant corroborating evidence for the reported apparition's authenticity.

The Lourdes apparitions were investigated and eventually approved by the Catholic Church, and the shrine that grew up around the reported site has since become one of the most visited Catholic pilgrimage destinations in the world, drawing millions of visitors annually including many seeking healing at its waters, so that the 1854 dogma and the 1858 apparitions are now closely linked in popular Catholic memory and devotional practice even though the doctrine itself was formally settled independently of, and prior to, any apparition claim.

The United States bishops formally placed the country under the patronage of the Immaculate Conception in 1846, eight years before the doctrine was defined as dogma, a dedication now expressed physically in the Basilica of the National Shrine of the Immaculate Conception in Washington, D.C., one of the largest Catholic churches in North America and a major site of pilgrimage on the feast day itself.