The Feast of the Immaculate Conception — a holy day of obligation — is the first of two important Marian feast days that fall during Advent. It celebrates the conception of Mary within the womb of St Anne and dates back to the seventh century for the Eastern Church and eighth century for the Western Church.

Two Franciscans helped develop the theology that Mary’s Immaculate Conception was necessary to ensure Jesus’ birth was also without original sin since children take on characteristics of both parents. Franciscan Father Don Miller noted in a reflection, that the angel Gabriel, speaking on God’s behalf, addresses Mary as “full of grace.” Her role in salvation history meant she had to be sinless from the outset.

The Catholic dogma that Mary, the mother of Jesus, was free from original sin from the moment of her conception and preserved from all sin throughout her earthly life was declared by Pope Pius IX in 1854. The feast is fixed nine months before the feast marking Mary’s birthday on Sept. 8. Our Lady of the Immaculate Conception is the patron of the United States and 10 other nations in South America, Africa, Asia and Europe.