A much-misunderstood feast. One can summarize the doctrine thus: In the Constitution Ineffabilis Deus of 8 December, 1854, Pius IX pronounced and defined that the Blessed Virgin Mary "in the first instance of her conception, by a singular privilege and grace granted by God, in view of the merits of Jesus Christ, the Saviour of the human race, was preserved exempt from all stain of original sin." That does not mean, of course, that Mary did not need to be redeemed. Mary is a redeemed creature, just as we all are; but in her case, God conferred a special grace, anticipating, so to say, the saving death and resurrection of our Lord Jesus Christ. Today we shall celebrate with joy this "holy light on earth's horizon", the first glimmering of the Rising Sun whom we shall welcome on Christmas Day. (Note: we have just added a Gregorian Chant radio button to our liturgical resources page. It is our intention [hope?] to expand the Plainsong Resources section over the next six weeks. If you have any links to suggest, please email us. We have also amended the corrupted links on our shopping and helping pages, many thanks to those who alerted us to the problem. Online donations via Paypal are limited to £100 so you don't give more than you intended!)