From this brief account by Luke, we can connect the gift of the Holy Spirit and the preaching of the gospel to those outside the Church, which had been formed by the coming of the Spirit. Later when the apostles are threatened and told to stop preaching the name of Jesus, they gathered for prayer and asked God to “grant to your servants to continue to speak your word with all boldness…And when they had prayed, the place in which they were gathered together was shaken, and they were all filled with the Holy Spirit and continued to speak the word of God with boldness” (4:29-31). There is an immediate confirmation by the Spirit, because it was what God wanted to do through them.
Are you making the connection? The coming of the Holy Spirit was, along with other reasons, intended to empower the apostles with preaching the gospel with boldness and He confirmed this in them by His filling them with His power. We cannot effectively preach the Good News with Him. It’s no wonder thousands were added to the Church! The question is whether we want to be filled by Him and as effective as they were in reaching those who have never heard?