The Feast of Holy Pentecost is celebrated each year on the fiftieth day after the Great and Holy Feast of Pascha 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 on the apostles on the Old Testament feast of Pentecost. 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 good news of salvation in Jesus Christ. The Feast also celebrates the culmination of the revelation of the Holy Trinity.
The account of Pentecost is found in the Acts of the Apostles. In Chapter two we are told that the Apostles were gathered together in one place. Suddenly, a sound came from heaven like a rushing wind, filling the entire house where they were sitting. Then, tongues of fire appeared, and one sat upon each one of Apostles. They were all filled with the Holy Spirit and began to speak in other languages as directed by the Spirit (Acts 2:1-4).
Background
This miraculous event occurred on the feast of Pentecost, celebrated by the Jews on the fiftieth day after the Passover as Shavuot, the culmination of the Feast of Weeks (Exodus 34:22; Deuteronomy 16:10). The Feast of Weeks began on the third day after the Passover with the presentation of the first harvest sheaves to God, and it concluded on Pentecost with the offering of two loaves of unleavened bread, representing the first products of the harvest (Leviticus 23:17-20; Deuteronomy 16:9-10).
The Jewish Encyclopedia points to the similarities between the Christian and Jewish Pentecost, as an outpouring of the spirit or the giving of the Law in seventy languages.
Since the Jewish Feast of Pentecost was a great pilgrimage feast, many people from throughout the Roman Empire were gathered in Jerusalem on this day. When the people in Jerusalem heard the sound, they came together and heard their own languages being spoken by the Apostles (Acts 2:5-6). The people were amazed, knowing that some of those speaking were Galileans, and not men who would normally speak many different languages. They wondered what this meant, and some even thought the Apostles were drunk (Acts 2:7-13).
Peter, hearing these remarks, stood up and addressed the crowd. He preached to the people regarding the Old Testament prophecies about the coming of the Holy Spirit. He spoke about Jesus Christ and His death and glorious Resurrection. Great conviction fell upon the people, and they asked the Apostles, “What shall we do?” Peter said to them, “Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins; and you shall receive the gift of the Holy Spirit” (Acts 2:38-39).
The Bible records that on that day about three thousand were baptized. The book of Acts goes on to say that the newly baptized continued daily to hear the teaching of the Apostles, as the early Christians met together for fellowship, the breaking of bread, and for prayer. Many wonderful signs and miracles were done through the Apostles, and the Lord added to the Church daily those who were being saved (Acts 2:42-47).
Orthodox Christian Celebration of the Feast of Pentecost
This great Feast of the Church is celebrated with the Divine Liturgy of Saint John Chrysostom on the Sunday that falls fifty days after the celebration of Pascha. On the day of the Feast, the Vespers includes kneeling prayers. During the days of Pascha, standing with the risen Christ, we have not knelt or prostrated; now the Church again resumes kneeling in prayer, intercession, and worship. On the Monday following the Feast, the Divine Liturgy is served in commemoration of the all-holy, life-creating and all-powerful Spirit, who is One of the Trinity, one in nature with the Father and the Son.
Prayer to the Holy Spirit
On this day, for the first time since Pascha, we resume saying the daily prayer: O Heavenly King, Comforter, the Spirit of Truth, Who art everywhere present and fillest all things; Treasury of blessings and Giver of life: Come and abide in us, cleanse us from every impurity and save our souls, O Good One.
Hymns of the Feast
Troparion: Blessed art Thou, O Christ our God, Who hast revealed the fishermen to be most wise by sending down upon them the Holy Spirit; and through them Thou hast caught the whole world in Thy net. Glory to Thee, O Lover of Mankind.
Kontakion: When the Most High came down and confused the tongues, He divided the nations. But when He distributed the tongues of fire, He called all to unity; therefore with one voice we glorify the Most Holy Spirit.
Readings for the Vigil
At Great Vespers
A reading from Numbers.
The Lord said to Moses: Gather to me seventy men of the elders of the people, whom you know to be elders of the people, and their scribes; and you shall bring to the Tent of Witness, and they shall stand there with you. And I shall come down and speak with you there, and I shall take of the Spirit which is upon you and place it upon them, and they shall bear the burden of the people with you, and you shall not bear them alone. And Moses gathered seventy men of the elders of the people, and stood them around the Tent. And the Lord came down in a cloud and spoke to Moses, and he took of the Spirit which was upon him and placed it upon the seventy men, the elders. But as the Spirit rested upon them, they too prophesied in the camp, and then did so no longer. And two men had been left behind in the camp; the name of one was Eldad and the name of the second was Modad, and the Spirit rested upon them; and they were of those who had been listed, but they had not come to the Tent; and they prophesied in the camp. And the youth ran and told Moses, and said to him: Eldad and Modad are prophesying in the camp. And Jesus, son of Navi, who was Moses’ assistant, his chosen one, said: My Lord Moses, stop them. And Moses said to him: Why, are you jealous for me? And who would not give that all the Lord’s people were prophets, whenever the Lord should put his Spirit upon them? (11:16-17, 24-29)
A Reading from the Prophecy of Joel.
Thus says the Lord: Children of Sion rejoice, and be glad in the Lord your God, because he has given you food for justice; and he will send the early and the latter rain for you, as before; and the threshing floors will be full of corn, and the presses overflowing with wine and oil. And I shall repay you for the years that the locust has devoured, the crawling locust, the consuming locust, the chewing locust and my great power which I sent against you. And eating you shall eat and be filled, and praise the name of the Lord your God, who has done wondrous things with you, and my people shall no longer be ashamed for ever. And you shall know that I the Lord your God am in the midst of Israel, and there is none beside me, and my people shall no longer be ashamed for ever. And it shall be after these things that I will pour out of my Spirit upon all flesh, and your sons and your daughters will prophesy and your elders will dream dreams and your youths see visions. And upon my servants and my maid servants I shall pour out of my Spirit in those days, and they will prophesy; and I shall show wonders in the heaven above and signs in the earth beneath, blood and fire and the vapour of smoke; the sun will be transformed to darkness and the moon to blood, before the great and manifest day of the Lord comes; and it shall be that everyone who calls on the name of the Lord will be saved. (2:23-32)
A Reading from the Prophecy of Ezekiel.
Thus says the Lord: I shall take you from among the nations and gather you from all the lands and bring you into your own land; and I shall sprinkle pure water upon you, and you will be purified from all your impurities and from all your idols, and I shall purify you; and I shall give you a new heart and I shall give you a new spirit; and I shall take away the heart of stone from your flesh and give you a heart of flesh; and I shall put my spirit in you and make you walk in my statutes and you shall keep my judgements and do them; and you shall dwell on the land which I gave to your fathers, and you shall be my people, and I shall be your God. (36:24-28)