The Feast of Holy Pentecost is celebrated each year on the fiftieth day after the Great and Holy Feast of Pascha (Easter) and ten days after the Feast of the Ascension of Christ. The Feast is always celebrated on a Sunday.
The Feast commemorates the descent of the Holy Spirit upon the Apostles on the day of Pentecost, a feast of the Jewish tradition. It also celebrates the establishment of the Church through the preaching of the Apostles and the baptism of the thousands who on that day believed in the Gospel message of salvation through Jesus Christ. The Feast is also seen as the culmination of the revelation of the Holy Trinity
Icon of the Feast
The icon of the Feast of Pentecost is known as "the descent of the holy spirit". it is an icon of bold colors of red and gold signifying that this is a great event. the movement of the icon is from the top to the bottom. at the top of the icon is a semicircle with rays coming from it. the rays are pointing toward the apostles, and the tongues of fire are seen descending upon each one of them signifying the descent of the holy spirit.
The building in the background of the icon represents the upper room where the Disciples of Christ gathered after the Ascension. The Apostles are shown seated in a semicircle which shows the unity of the Church. Included in the group of the Apostles is Saint Paul, who, though not present with the others on the day of Pentecost, became an Apostle of the Church and the greatest missionary. Also included are the four Evangelists—Matthew, Mark, Luke, and John—holding books of the Gospel, while the other Apostles are holding scrolls that represent the teaching authority given to them by Christ.
In the center of the icon below the Apostles, a royal figure is seen against a dark background. This is a symbolic figure, Cosmos, representing the people of the world living in darkness and sin, and involved in pagan worship. However, the figure carries in his hands a cloth containing scrolls which represent the teaching of the Apostles. The tradition of the Church holds that the Apostles carried the message of the Gospel to all parts of the world.
In the icon of Pentecost we see the fulfillment of the promise of the Holy Spirit, sent down upon the Apostles who will teach the nations and baptize them in the name of the Holy Trinity. Here we see that the Church is brought together and sustained in unity through the presence and work of the Holy Spirit, that the Spirit guides the Church in the missionary endeavor throughout the world, and that the Spirit nurtures the Body of Christ, the Church, in truth and love.
taken from : http://www.goarch.org/en/special/listen_learn_share/pentecost/learn/
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