Pentecost (Ancient Greek: πεντηκοστή [ἡμέρα], pentekostē [hēmera], "the fiftieth day") is one of the prominent feasts in the Christian liturgical year. The feast is also called Whitsun, Whitsunday, Whit Sunday, and Whitsuntide, especially in the United Kingdom. Pentecost is celebrated seven weeks (49 days) after Easter Sunday, hence its name.[1] Pentecost falls on the tenth day after Ascension Thursday. Historically and symbolically related to the Jewish harvest festival of Shavuot, which commemorates God giving the Ten Commandments at Mount Sinai fifty days after the Exodus, Pentecost now also commemorates the descent of the Holy Spirit upon the Apostles and other followers of Jesus as described in the Book of Acts, Chapter 2 in the New Testament. For this reason, Pentecost is sometimes described as "the Church's birthday". The Pentecostal movement of Christianity derives its name from this biblical event.