It is very important for us to grasp that Pentecost is not a one-off event, but is supposed to be normative for the life of Christ's Body, the Church. As we continue reading through the early chapters of Acts it is often written about those who speak in Jesus' name, before they speak, that they are filled with the Holy Spirit - Peter before the Sanhedrin in Acts 4:8; the Jerusalem Christian community praying for boldness to proclaim Christ in the face of hostility in Acts 4:31; the seven Greek-speaking men venerated as the Church's first deacons had to be "filled with the Spirit and wisdom" as a requirement for office (Acts 6:3b); one of these men, Stephen, is described from the first time he is mentioned as "a man filled with faith and the holy Spirit" (Acts 6:5b), who, just before his martyrdom, "filled with the holy Spirit, looked up intently to heaven and saw the glory of God and Jesus standing at the right hand of God" (Acts 7:55).
Pentecost is the theological version of what goes up must come down. Jesus ascends and the Holy Spirit descends, just as Christ promised. During the Last Supper discourse in St. John's Gospel Jesus said, "But I tell you the truth, it is better for you that I go. For if I do not go, the Advocate will not come to you.e But if I go, I will send him to you" (John 16:7). A bit earlier on Jesus tells Philip, who asks Him to show them the Father, "whoever believes in me will do the works that I do, and will do greater ones than these, because I am going to the Father" (John 14:12).