08/12/2025
December 8, Celebration of Feast of Immaculate Conception. Just to clarify, the Immaculate Conception is the celebration of the day Mary was conceived without original sin by her elderly mother St. Anne, wife of elderly St. Joachim. So, Mary was conceived by St. Anne without original sin, the same way St. Mary conceived Jesus.
An angel appeared before the chaste elderly couple Anne and Joachim, in separate places, announcing the conception of a child, who will be called Mary, through a miraculous blessing from God as an answer to their prayers.
The Feast of Immaculate Conception (also called The Conception of St. Anne in earlier years) was initially a celebration of Mary’s purity by devoted Christians in early years. The celebration gradually became widespread in many Christian churches. On December 8, 1854, Pope Pius IX of Roman Catholic Church officially defined the doctrine in Mary’s Immaculate Conception proclaiming Mary was born pure unstained by original sin, celebrating the Feast of Immaculate Conception from then onwards every December 8.
Conceived on December 8, so using the currently used calculator to know the estimated date of birth if conception date is known, just add 266 days. Birth would be expected by August 31. Anyway, it’s all symbolic celebrations. Nobody could really tell the exact dates of conception and birth of St. Mary. Obviously, nine months counted from December 8 as the conception date, would be September 8 which became the celebration of Mary’s birthday - the Notre Dame Day.
By the way, all of those narratives are based on the Roman Catholic church teachings. Other Christian church denominations or other religious beliefs may have other story. Nice to always show respect to whatever version of story everyone has; nobody can tell the exact details of the story, afterall🙏