While the actual event of the Assumption of Mary into Heaven is not recorded in the Scriptures, there is a biblical basis for the teaching that, considered as a whole, confirms Catholic teaching as both fitting and in keeping with biblical principles. Let’s ponder this feast in stages:
The Assumption Explained – To be “assumed” means to be taken up by God bodily into Heaven. As far back as the Church can remember we have celebrated the fact that Mary was taken up into Heaven. We do not just acknowledge that her soul was taken to Heaven, as is the case with the rest of the faithful who are taken there (likely after purgation); rather, Mary was taken up, soul and body, after her sojourn on this earth was complete. There is no earthly tomb containing her body, neither are there relics of her body to be found among the Christian faithful. This is our ancient memory and what we celebrate today, Mary was taken up, body and soul, into Heaven.
The Assumption Exemplified – While Mary’s Assumption is not described in Scripture, several other “assumptions” are; thus the concept itself has a biblical basis. The actual event of the Assumption is not described in Scripture. However, there are “assumptions” recorded in the Scriptures and thus the concept is biblical.
Enoch – Enoch walked with God; then he was no more, because God took him away(Gen. 5:24). By faith Enoch was taken up so that he should not see death; and he was not found, because God had taken him. Now before he was taken he was attested as having pleased God (Hebrews 11:5).
Elijah – And as they still went on and talked, behold, a chariot of fire and horses of fire separated the two of them. And Elijah went up by a whirlwind into heaven … And he was seen no more (2 Kings 2:11).
Moses – Some say that because the location of Moses’ grave is not known, he too was taken up into Heaven. We read in Monday’s first reading at daily Mass: He was buried in Moab, in the valley opposite Beth Peor, but to this day no one knows where his grave is (Dt. 34:6). The text of course does not say that his body was taken up, and if it was, it occurred after death and burial. The Book of Jude hints at this: But even the archangel Michael, when he was disputing with the devil about the body of Moses… (Jude 1:9). Some further credibility is lent to the view of Moses being assumed by the fact that he appears with Elijah in the account of the Transfiguration. Some of the Church Fathers also held this opinion. Further, there is a Jewish work from the 6th century A.D. entitled The Assumption of Moses. In the end, though, the assumption of Moses is not officially held by the Church.
Read more at Archdiocese of Washington.