33 AD
Pentecost, occurring fifty days after Easter (hence the name from the Greek for 'fiftieth'), marks the descent of the Holy Spirit upon the Apostles and the birth of the Church. The disciples were gathered together in the upper room in Jerusalem when 'suddenly there came from heaven a sound like a rushing violent wind, and it filled the entire house where they were sitting. And divided tongues as of fire appeared to them and rested on each one of them. And they were all filled with the Holy Spirit and began to speak in different tongues, as the Spirit gave them ability to speak' (Acts 2:1-4).
The crowds of Jerusalemβpeople from every nation under heavenβheard the disciples speaking in their own languages about 'the mighty works of God.' Peter rose and delivered the first Christian sermon, proclaiming the Resurrection and calling for repentance and baptism. About 3,000 people were baptized that day, and the community of believers devoted themselves 'to the apostles' teaching and fellowship, to the breaking of bread and the prayers' (Acts 2:42).
The Catholic Church sees Pentecost as the fulfillment of Jesus' promise to send the Advocate (John 14:16-17; 15:26; 16:7). The Holy Spirit empowers the Church for mission, guides her into all truth, and unites believers across every barrier of language, culture, and nation. Pentecost is the birthday of the Church. Key Scripture: Acts 2; John 20:22; John 14-16; Romans 8:14-17; CCC 694-696, 731-740