Today, Catholics celebrate the Assumption of the Blessed Virgin Mary. This event is when the Virgin Mary was taken up into Heaven, at the end of her life. At this time, both her body and her soul.
The Bible teaches us that death is a result of sin. It says, "through sin, death entered the world" and again, "the wages of sin are death". The Virgin Mary born without sin, and she never sinned during her life. Therefore, it was not necessary for her to die, as it was impossible for her body to undergo corruption and decay. However, she wished to follow the example of her divine son, and she too passed through the dark portal of death before being taken up into Heaven.
St. John Damascene is sometimes called the Doctor of the Assumption, because he wrote a lot about it in the 600's. While passing on the ancient traditions about the death of Mary, he says that all of the apostles were present at her death bed in Jerusalem, except for St. Thomas. Thomas arrived three days later, and he requested to see her body. "The body could nowhere be seen, and a delicious perfume filled the empty tomb.
The apostles then became convinced that as God had preserved the body of Mary
free from sin before, in, and after the birth of His Son, He was pleased
likewise, after her death, to preserve that same body from corruption, and to
glorify it in heaven."