Do you now?
The Assumption? What about it?
We could look at what NewAdvent.org admits (my comments are in parenthesis and/or bolded).
" The fact of the Assumption
Regarding the day, year, and manner of
Our Lady's death,
nothing certain is known. The earliest
known literary reference to the Assumption is found in the Greek work
De Obitu S. Dominae. (
that's c300-500ad)
Catholic faith, however, has always derived our
knowledge of the
mystery from
Apostolic Tradition.
Epiphanius (d. 403) acknowledged that he
knew nothing definite about it (Haer., lxxix, 11). (
That's an admittance of drawing information from Tradition and that Tradition just said we don't know.) The
dates assigned for it vary between three and fifteen years after
Christ's Ascension. (
Pure speculation based on vapor.) Two cities claim to be the place of her departure:
Jerusalem and Ephesus. Common consent favours
Jerusalem, where her
tomb is shown; but some argue in favour of Ephesus. The first six centuries did not
know of the
tomb of Mary at
Jerusalem.
The belief in the corporeal assumption of Mary is founded on the apocryphal treatise De Obitu S. Dominae, bearing the name of St. John, which belongs however to the fourth or fifth century. It is also found in the book De Transitu Virginis, falsely ascribed to St. Melito of Sardis, (and a Pope declared that book spurious, yet it's still drawn from) and in a spurious letter attributed to St. Denis the Areopagite. If we consult
genuine writings in the
East, it is mentioned in the
sermons of
St. Andrew of Crete, (c740ad)
St. John Damascene (c757ad), St. Modestus of Jerusalem and others. In the
West,
St. Gregory of Tours (De gloria mart., I, iv) mentions it first (c600). The
sermons of
St. Jerome and
St. Augustine for this
feast, however, are spurious.
St. John of Damascus (P.G., I, 96) thus formulates the
tradition of the
Church of
Jerusalem:
Today, the
belief in the corporeal assumption of
Mary is universal in the
East and in the
West; according to
Benedict XIV (De Festis B.V.M., I, viii, 18) it is a
probable opinion, which to deny were impious and
blasphemous.
Regarding the origin of the
feast we are
also uncertain. ... "
But we have to marvel that something clearly admitted as uncertain is required for salvation.
The very early Church would reject the 'assumption of Mary' dogma out of hand because it arose apart from scripture and apostolic teaching. It arose late. It arose from spurious associations.