Opening the Word: Pentecost Sunday celebrates unity brought by Holy Spirit

“Spirit and fire are united — a true miracle, air and fire are joined together — awesome sight!” 

So wrote the sixth-century Church Father, St. Romanus the Melodist, in a kontakion, or hymn, celebrating Pentecost. In another verse, he wrote, “Do you, then, dearly beloved, stand and simply observe the fire, which the One who is in heaven has sent from on high.”  

His beautiful hymn emphasizes three essential truths about the Holy Spirit, each revealed in today’s readings. Let’s begin with John’s account of the apostles in the upper room, which describes a frightened group of men behind locked doors. Despondent and shattered, they were like lifeless clay or dry bones. But when Jesus entered, they rejoiced, and when he breathed upon them, they came alive with the gift of the Holy Spirit (see Gn 2:7; Ez 37:5). This shows how closely united are the death-destroying resurrection of Christ and the life-creating gift of the Holy Spirit. 

Seven weeks later, the disciples were once again in the upper room, but filled with expectancy, not dread. Again, the presence of God came suddenly, this time with a noise like a strong wind and what appeared to be “tongues of fire.” On Pentecost, God’s presence was represented by wind and fire, and so began the pilgrimage of the newly revealed people of God, the Church. The Catechism of the Catholic Church states, “By his coming, which never ceases, the Holy Spirit causes the world to enter into the ‘last days,’ the time of the Church, the Kingdom already inherited though not yet consummated” (No. 732). 

The second truth is that for in the Church, as St. Paul told the Corinthians, the “manifestation of the Spirit is given for some benefit.” The Holy Spirit is manifest — it acts and empowers — through the Sacrament of Baptism, which unites man with the mystical Body of Christ. This transformation was dramatically evident in the upper room on Pentecost; the Spirit-filled disciples, touched by tongues of fire, were able to “speak in different tongues” and “to proclaim.” And what was proclaimed that day? The gospel of Jesus Christ, culminating in Peter’s exhortation to repent and be baptized, so “you will receive the gift of the holy Spirit” (Acts 2:38). 

That call to repentance was also a call to unity. At Babel, men desired to establish unity and dominion through human power and ingenuity by building a great city and tower (see Gn 11:1-10). The third truth is that at Pentecost, God established unity and peace through the Holy Spirit, revealing to the world himself and his household, “the church of the living God, the pillar and foundation of truth” (1 Tm 3:15). The Catechism states of Pentecost: “On that day, the Holy Trinity is fully revealed” (No. 732). God is one but also Triune: Father, Son, and Holy Spirit. He is perfect unity, but also perfect relationship and communion (Nos. 253-6). The unity and catholicity of the Church is rooted in this great mystery of the Trinity. And from it, St. Paul wrote, flows a real and authentic diversity of gifts, service and workings, for “we were all given to drink of one Spirit.” 

St. Romanus, at the conclusion of his hymn, asked, “Why, then should we be afraid of a flame that does not burn?” This solemnity is a call to repentance and unity, as well as to joy and peace, each given by the All-Holy Spirit. 

Carl E. Olson is the editor of