If you are looking for direct and express scriptural proof of this dogma you will not find any as Mary’s assumption was not recorded in scripture. However, Pope Pius XII formally defined the dogma of the assumption in his apostolic letter Munificentissimus Deus (MD) on November 1, 1950: "the Immaculate Mother of God, the ever Virgin Mary, having completed the course of her earthly life, was assumed body and soul into heavenly glory” (MD 44).
To understand the pope’s authority to make such a declaration see Papal Infallibility.
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