Pentecost Sunday commemorates the day the Holy Spirit descended upon the early church, fulfilling the promises of Jesus and John the Baptist. After Jesus’ resurrection and ascension, the disciples gathered in Jerusalem as instructed. On Pentecost, the Holy Spirit filled them with power, symbolized by tongues of fire, enabling them to boldly spread the gospel—marking the birth of the Christian church. This day reminds believers that the same Spirit lives within them, uniting all in Christ, empowering them for service, and continuing God’s promise to all who are called.