Pentecost comes from the Greek pentekoste, which means "fiftieth." At Pentecost we celebrate the gift of the Holy Spirit after Jesus' ascension, thus inaugurating the mission of the Church. Readings are often from the book of Acts, since the early Church, empowered by the Holy Spirit, is the best witness to the resurrection. Bright red is the color for this season. The Day of Pentecost ends the Easter cycle.