God’s gift of the Holy Spirit to the Church is not only original, unique, and exclusive, it is also permanent. This gift is as irrevocable as the Incarnation itself. Much as the event of the Word’s enfleshment irrevocably links the Second Person of the Holy Trinity to the human race, the event of Pentecost joins the Third Person of the Holy Trinity permanently to the Church. Both conjunctions are irreversible.
The Holy Spirit will never abandon the one, holy, catholic, and apostolic Church. Although individual believers may make shipwreck of the faith (1 Timothy 1:19), the ship of the Church will never sink. And although individual churches may suffer the removal of their lamp stands (Revelation 2:5), the Church herself remains infallibly the dwelling of God with men.
Three things in the Church are inseparable: the Resurrection of Christ, the gift of the Holy Spirit, and the Church’s authority to forgive sins. Because the power of sin was destroyed by what God accomplished in Christ, the remission of sins pertains to the essence of the Gospel.
The Evangelist John made clear this inseparability when he described the first appearance of the risen Christ to the assembled Church:
“During the evening on that same day-day one of the week-when the doors were shut where, out of fear for the Jews, the disciples were assembled, Jesus came and stood among them and said to them, ‘Peace to you.’ When he had said this, he showed them his hands and side. Seeing the Lord, the disciples rejoiced. So Jesus said to them again, ‘Peace to you! As the Father has sent me, I also send you.’ And saying this, he breathed and said to them, ‘Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain them, they are retained’ (John 20:19-23).
The apostolic authority to forgive sins is presented here as pertinent to the very mission of the Church: As the Father has sent me, I also send you.”
The Resurrection of Christ is proclaimed, therefore, not just as a past event but also as the source of an abiding power within in the Church. The forgiveness of sins is a present and permanent operation of the Holy Spirit, who is inseparably united to God’s People. It is the Holy Spirit who preserves in the Church the authority to remit—in God’s name—all the sins the Lamb of God took away by his Passion, death, and Resurrection.
In preaching what God accomplished in the death and Resurrection of Christ, the Church also summons sinners to the forgiveness made available by that accomplishment. The two things are, as it were, the two halves of the Gospel: “Thus it is written  that the Messiah should suffer and to rise from the dead on the third day and  that repentance and remission of sins should be preached in his name to all nations” (Luke 24:46-47).
When the Holy Spirit does descend on the Church, we see this juxtaposition exactly. The apostolic word first declares, “This Jesus God has raised up” (Acts 2:32), and then, as a moral necessary consequence, “Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins; and you shall receive the gift of the Holy Spirit” (2:38).
Because the Holy Spirit confers the authority to forgive sins, it is hardly surprising that the Holy Spirit also calls men to repentance. This summons of the Spirit appears in John’s letters to the seven churches:
To Ephesus: “Repent and do the first works, or else I will come to you quickly and remove your lampstand from its place-unless you repent. . . . He who has an ear, let him hear what the Spirit says to the churches.”
To Pergamos: “Repent, or else I will come to you quickly and will fight against them with the sword of my mouth. He who has an ear, let him hear what the Spirit says to the churches.”
To Laodicea: “Therefore be zealous and repent. . . . He who has an ear, let him hear what the Spirit says to the churches.”