The Assumption of the Virgin Mary or the Dormition of the Theotokos is both an important feast day and teaching in the Roman Catholic and many Eastern Catholic or Orthodox churches. It also may be celebrated to some degree and with some differences in Anglican and some other Protestant churches. It commemorates the concept that Mary the mother of Jesus Christ was bodily assumpted/assumed into heaven, without undergoing the corruption of the body that follows death and which is part of the punishment for original sin. There are arguments between denominations on whether this assumption occurred before or after Mary died
There are not that many scriptural references to the death or Assumption of the Virgin Mary, though the idea has been discussed for centuries. It has also been a basic teaching of the many denominations that celebrate this time, and a matter of preoccupation for theologians dating backing to the 400s CE. Much of the argument regarding whether this was true teaching centered on whether Mary died prior to being assumed, but by about the 7th century, celebration of the Assumption of the Virgin Mary was common in a number of churches.
Though this celebration became accepted over numerous years, an interesting twist occurred in Roman Catholicism in the mid 20th century. Pope Pius XII declared that the teaching was absolutely correct and infallible. This meant, that at least in Roman Catholic belief, the Assumption of Mary is not only a teaching but part of spiritual belief. To an extent fully believing that Mary was assumed into heaven is just as important as important as belief in the resurrection of Christ. Pius XII did not answer the question of whether Mary died first, and that matter is still open for debate.
The declaration by the pope made the Assumption of the Virgin Mary one of the most important days in the Catholic calendar and it is designated a Holy Day of Obligation, which means people must attend church under most circumstances. Celebration of the event in Eastern Orthodox churches when it is observed may be even more involved. Dormition (death or falling asleep) of the Theotokos (mother of God) may be preceded by two weeks of fasting or abstention from most meat and dairy products. This is followed by a feast day on August 15, and as in Roman Catholicism, Mary’s assumption into heaven is greeted with enthusiasm instead of grief, since she and her son, are the promise for all people that life does not end with death. One important difference, however, is that Orthodox churches tend to believe Mary died, and rose on the third day fully to heaven.
The tradition of celebrating on August 15 in much of Europe predates Christianity. This date was a harvest festival that honored Roman Gods, particularly Diana, who watched over the harvest in some interpretations. Replacing an old holiday with a new one that has some slight relationship to it is certainly not a new convention. Other feast days like Easter and Christmas have pagan antecedents too.
A number of countries make more of this day than simply calling it a holy day. It may still be called a holiday by heads of state, and this tradition can be found in several European countries, in South American countries, and in a few African countries. Some countries or cities hold elaborate festivals.
Many people who are non-Christian wonder why this particular teaching in all of its incarnations is so important. As mentioned before, it is the promise of Jesus’ teachings fulfilled. Belief in the Assumption of the Virgin Mary is connected to belief in the afterlife, that Jesus did really “go and prepare a place for you,” (John 14:3). Moreover, many feel emotionally connected to this day because it represents reunion between Christ and his mother.