Immaculate Conception - Dec 8th

Immaculate conception -- or the dogmatic teaching that Mary
was born without original sin -- dates back to the early church.What was simply known as the Feast of the Conception (celebrating St Anne's having conceived her daughter, Mary) led
to the belief that Mary herself must have been born without
original sin in order to give birth to Jesus Christ. It is designated a holy day of obligation when all Roman
Catholics are required to attend mass.