Why Do Catholics Believe That Mary Was Assumed into Heaven? *
The Second Book of Kings tells how the prophet Elijah was taken up bodily into heaven (see 2:1-12). Scripture notes, in fact, several unusual departures from this world to the next after a life lived close to God. Not only Elijah, but also Enoch and those who came out of the tombs at Christ's death wee all received bodily into heaven before the final, universal resurrection of the dead that is still to come (See Gn 5:24; Heb 11:5; Mt 27:50-53).
Mary's bodily assumption, as it's called, into the glory of heaven was a singular privilege, reserved for the mother of our Lord, far beyond what these others experienced. Nevertheless, in the biblical record of these earlier events we see that there's nothing "unbiblical" about the claim that God has chosen to take a holy person to himself in a special way.
Is Mary's assumption described in the Bible? No, but that doesn't mean it didn't happen. the death of St. Joseph isn't described in Scripture, either, though it's certain that this important event took place within the years chronicled by the gospels. In fact, many events even from the life of our Lord himself were not recorded in Scripture (see Jn 21:21:25). The assumption of Mary is only one of many significant events in the life of the early Church that have been remembered and witnessed to by ancient Tradition.
According to an ancient account of the life of St. Theodosius, the feast of our Lady's assumption was already being celebrated in Palestine in the 400s. This indicates that by the fifth century the Assumption was already a well-established conviction of Christ's followers in the land where he and his mother had lived. In 1950, after many centuries of Christian testimony to this reality, Pope Pius XII defined it as a dogma of the Church.
The Assumption is consistent with Mary's role as the Theotokos ("God-bearer") and immaculate sinless one, who was granted a singular divine grace to bear God himself in her body. If indeed she was free from sin, then it follows that she would not have to undergo the decay of death, which was the penalty for sin (see Gn 3:16-19). If not for the fall of the human race, no one would have died. Mary is the exception, for very good reason, and the forerunner of the resurrection that all who belong to Christ will experience (see 1 Cor 15:12-23).
Other related scriptures: Ps 16:10; Lk 1:28-31 (with Zep 3:14-17); 2 Cor 12:2-4; Heb 2:14-18; Rv 12:1, 5, 17.
Catechism of the Catholic Church: 966; 974.
*Quoted from The New Catholic Answer Bible. Wichita, Kansas, Fireside Catholic Publishing, 2005. www.firesidecatholic.com
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