The term derives from pent-ekost-e (lit. 50th), the Greek name for the Jewish Feast of Weeks at the close of the grain harvest 50 days after Passover and Unleavened Bread (see Tob. 2:1). In the early church, Pentecost at first designated the whole period of 50 days from Easter;* only later did it refer particularly to the 50th day, which became a feast in its own right.
The 50 days celebrating Christ’s resurrection* were the most joyful season (Tertullian), one great Sunday (Athanasius); there was no kneeling for prayer but only standing (to mark the heavenly location of believers in Christ, in anticipation of the general resurrection); and there was no fasting (a foretaste of the heavenly banquet with the messianic bridegroom). In the 4th century, the 50th day was regarded as the seal of the period, with Christ’s ascension and the Spirit’s descent as its twin themes. At the turn into the 5th century, the two distinct feasts emerged of Ascension (40 days after Easter; see Acts 1:1-11) and Pentecost (see Acts 2:1-4). The vigil of Pentecost became a baptismal occasion, and the white robes of the baptized account for the English Whitsunday.
First in sectarian Judaism in the intertestamental period, and then in rabbinic Judaism by the 2nd and 3rd centuries of the Christian era, the Feast of Weeks has become associated with the law-giving and covenant* of Sinai. Sermons at the feast of Pentecost by Christian preachers of the 5th century relate the new covenant of the Spirit to the old covenant of the law. Furthermore, the gift of the Holy Spirit* for apostolic preaching is considered as a reversal of Babel , bringing unity* and catholicity* to the church* and its mission.* An ancient Latin collect prays: Make the peoples dispersed by the division of language to be joined by your heavenly gift in the united confession of your name.
In the modern ecumenical movement, Pentecost became a time of special prayer for Christian unity. The preparatory conference of Faith and Order* at Geneva in 1920 appealed for an annual week of prayer for the unity of the church, ending with Whitsunday. In 1941 F&O changed its dates to the 18-25 January octave, but the Pentecost time remains favoured in some parts of the world (see Week of Prayer for Christian Unity ). The presidents of the WCC send a Pentecost message to member churches every year.
The text above is extracted from Dictionary of the Ecumenical Movement 2 nd Edition , published by World Council of Churches (courtesy of World Council of Churches)