An Official Belief

On November 1, 1950, Pope Pius XII, exercising papal infallibility, declared in an Apostolic constitution known as the Munificentissimus Deus that it is a dogma of the Church "that 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." As a dogma, the Assumption is a required belief of all Catholics. Anyone who publicly dissents from the dogma, Pope Pius declared, "has fallen away completely from the divine and Catholic Faith."

While members of the Eastern Orthodox church believe in the Dormition, they object to the papal definition of the dogma, seeing it as unnecessary, since belief in Mary's bodily assumption, tradition holds, goes back to apostolic times.