How did the Church determine that September 8 is the birthday of our Blessed Mother?

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How did the Church determine that September 8 is the birthday of our Blessed Mother?


Usually, the Church assigns dates for particular feasts. The assignments can be based on the date of a saint’s death, a date that has special meaning in the saint’s life, or some other meaningful date. In the case of the Nativity of the Blessed Mother, September 8 is the date that follows nine months after December 8, on which date the Church celebrates the feast of the Immaculate Conception of Mary.

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By Raphael Benedict

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  1. That doesn’t really answer the question. On what basis does the Church claim to know what day of the year Mary was either conceived or born? On what basis does it claim to know what day Christ was conceived or born? In the latter case we do have a couple of clues: shepherds staying awake at night to protect their sheep which they only did in a certain season of the year; and the likelihood that the star of Bethlehem was most likely a planetary conjunction whose timing is firmly established by science. But the fact is we really don’t know much about Mary’s life apart from what is mentioned in the Bible and a few insights from Tradition.

    1. The only written source would be a work called the “Protoevangelium of James” which the Church considers apocryphal. It comes from the early 2nd c. A.D., contains the names of Mary’s parents, and the nativity of Mary. But as far back as the 4th century, first in the East, then later in the West, we have the Church celebrating Mary’s birthday in early September. But you are right, there is precious little that we know for sure about the her life.
      As far as Christmas, we also have the historical reckoning of St. Luke to go along with what you mentioned already. And I’ve always like to think that the Apostles, after the Resurrection, may have asked Mary about when the Lord’s birthday was. I’ll bet she remembered. 😉

  2. If December 8is the feast of the immaculate conception of Mary they just went 9months from that. Also even though the church may not know the exact date of the birth of Mary, we as the church give her the honor of those days. We dont need an exact date anyway… she is now Queen of heaven and earth… she is outside normal time and celebrating on an exact date is not the least of worries.
    Just like my birthday… if i going to have a celebration for it, it DONT have to be on the day of my birthday, this can be cause if it is no one will show up cause they already got something planned or will be working… so celebrate whenever is convenient…

    1. Philip,
      I’m not certain on the when, I could give a rough estimate (~33 A.D.-~90 A.D.) since both Scripture and Tradition tell us that Mary was taken in by John the Apostle, and we can guess that she didn’t outlive him.
      The where is probably either in Ephasus (where John lived) or Jerusalem. There is a story from the Eastern Romans called the “Dormition” which says that when the Virgin lay near death, all the surviving Apostles were suddenly gathered at her bed. The Church teaches that before earthly death could corrupt her, she was Assumed into heaven.
      The how… she was old? There isn’t going to be any guess better than that one. If John or one of the other Apostles wrote about it, that writing has remained lost.

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