The Feast of Pentecost is said to be the visible establishment of the New Covenant Church, and its mission to proclaim the Gospel of Christ. While the Holy Spirit filled Mary, the Apostles, and other disciples interiorly, there were three visible signs that correspond to the optional readings for this feast day.
The first sign was the rushing of a mighty wind. This not only caught the attention of the pilgrims in Jerusalem present for the Feast of Weeks, but it also ties back to God giving the law to Israel on Mt. Sinai (Exodus 19). While Israel struggled to keep God’s law, we now see a fulfillment of the prophecy in Ezekiel (36:27) that God will pour His Spirit
within us to enable us to keep His statutes.
The second sign was the tongues of fire that settled on each of those gathered in the Upper Room. These fiery tongues gave visible evidence that the Holy Spirit had descended upon them, and Christ’s promise was fulfilled. They now had the courage to proclaim the risen Lord, and this corresponds to the reading from Joel (3), “… let the weak say I am a warrior”.
The third sign was the Apostles speaking in foreign languages, which they had not learned through normal means. This corresponds to the reading on the Tower of Babel (Gen. 11), and the undoing of the division in language caused by sin, pride, and ignoring God as Creator. This sign shows that Christ came to gather all people, who are willing, into His Church regardless of their differences in language and culture. “And suddenly a sound came from heaven like the rush of a mighty wind, and it filled all the house where they were sitting. And there appeared to them tongues as of fire, distributed and resting on each one of them. And they were all filled with the Holy Spirit and began to speak in other tongues, as the Spirit gave them utterance.” – Acts 2: 2-4