The Feast of the Dormition of Our Most Holy Lady, the Theotokos and Ever-Virgin Mary is celebrated on August 15 each year. The Feast commemorates the repose (dormition and in the Greek kimisis) or "falling-asleep" of the Mother of Jesus Christ, our Lord. The Feast also commemorates the translation or assumption into heaven of the body of the Theotokos.
By John Fotopoulos
A common misperception among Orthodox Christians is that Orthodox Easter (i.e. Pascha) often occurs so much later than Western Christian Easter because the Orthodox Church abides by the rules for calculating the date of Pascha issued by the 1st Ecumenical Council at Nicaea in AD 325. Another element of this misperception is the belief that the Orthodox Church must wait for Passover to be celebrated by the Jewish community before Pascha may occur. Despite these views being held by so many Orthodox Christians, as well as being promoted in popular essays written by some Orthodox priests, they are inaccurate. The reason why Orthodox Pascha frequently occurs so much later than Easter celebrated by Roman Catholics and Protestants is neither because the Orthodox Church follows the Paschal formula of Nicaea, nor is it because the Western Churches fail to adhere this formula. It is also not because the Orthodox Church must wait for the Jewish celebration of Passover. Rather, Orthodox Pascha frequently occurs later than Western Easter because the Orthodox Church uses inaccurate scientific calculations that rely on the inaccurate Julian Calendar to determine the date of Pascha for each year. Some background information is necessary to help explain precisely what the problems are.