The Old Testament Feast of Pentecost or Shavuot has many names in the Bible: the Feast of Weeks, the Feast of Harvest and the Latter Firstfruits. Celebrated on the fiftieth day after Passover, Shavuot is traditionally a joyous time of giving thanks and presenting offerings for the new grain of the summer wheat harvest in Israel.

Traditional Jews light candles, recite blessings, adorn their homes and synagogues with greenery, eat dairy foods, study the Torah and attend Shavuot Services. One theory on why Jews customarily eat dairy foods such as cheesecakes and cheese blintzes on Shavuot is that Jewish law was compared to “milk and honey” in the Bible. The tradition of decorating with greenery on Shavuot represents the harvest and the Torah’s reference as the “tree of life”.

In the New Testastment Church, Pentecost is celebrated on the fiftieth day after the Resurrection, commemorating the outpouring of the Holy Spirit on the apostles and the giving of grace and wisdom by God. Continuing the Jewish tradition, the faithful in Orthodox Churches decorate their churches and homes with greenery and flowers on this feast, symbolic of the renewal of the earth and new life in the grace of the Holy Spirit.

(Source: www.orthodoxcatholicmonastery.com/2017/06/03/the-jewish-feast-of-pentecost-shavuot)