Catholic Commentary
The Response of the Crowd: Repentance, Baptism, and the First Harvest
37Now when they heard this, they were cut to the heart, and said to Peter and the rest of the apostles, “Brothers, what shall we do?”38Peter said to them, “Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of sins, and you will receive the gift of the Holy Spirit.39For the promise is to you and to your children, and to all who are far off, even as many as the Lord our God will call to himself.”40With many other words he testified and exhorted them, saying, “Save yourselves from this crooked generation!”41Then those who gladly received his word were baptized. There were added that day about three thousand souls.
Three thousand people were baptized in a single day not because they heard a compelling argument, but because they were cut to the heart—and they knew exactly what to do.
In the immediate aftermath of Peter's Pentecost sermon, the crowd is pierced with conviction and cries out for guidance. Peter's response — repent, be baptized in the name of Jesus Christ, receive the Holy Spirit — is the Church's first formal proclamation of the sacramental path of salvation. About three thousand are baptized that day, marking the first great harvest of souls and the visible birth of the Christian Church.
Verse 37 — "Cut to the heart" The Greek κατενύγησαν (katenygesan) — translated "cut" or "pierced" to the heart — is a strong, almost violent term connoting a sharp, sudden compunction. This is not mere intellectual assent but the deep interior wound that precedes genuine conversion. Luke uses this word nowhere else in Acts; its singularity signals a moment of unrepeatable intensity. The crowd addresses Peter and the apostles as "Brothers" (ἄνδρες ἀδελφοί), a form of address that signals both respect and a dawning sense of solidarity — they are beginning to see themselves as part of the same family of Israel now confronted by its Messiah. Their question, "What shall we do?" (τί ποιήσωμεν;), echoes the identical question posed to John the Baptist by crowds, soldiers, and tax collectors (Luke 3:10–14), linking the ministry of Jesus' forerunner to its fulfillment at Pentecost. It is the question of someone who knows they must act, not merely believe.
Verse 38 — "Repent and be baptized … in the name of Jesus Christ" Peter's answer is tightly structured around four elements: (1) Repentance (μετανοήσατε) — a genuine interior turning, a change of mind and heart (metanoia), not merely remorse. This precedes baptism and is its necessary precondition. (2) Baptism in the name of Jesus Christ — Christian baptism is distinguished from John's baptism precisely by being "in the name of Jesus Christ," invoking the full authority and person of the risen Lord. The formula here does not contradict the Trinitarian formula of Matthew 28:19; rather, it specifies the Christological focus of the rite. (3) For the forgiveness of sins (εἰς ἄφεσιν τῶν ἁμαρτιῶν) — the preposition εἰς indicates purpose or result: baptism is ordered toward, and effects, the forgiveness of sins. This is a direct, unambiguous statement of baptismal regeneration. (4) The gift of the Holy Spirit — the Spirit is not merely a subsequent bonus but the promised inheritance, the eschatological gift of the new covenant (cf. Joel 2:28; Ezek 36:26–27). The sequence of repentance → baptism → Spirit reception will be repeated, with variations, throughout Acts (8:14–17; 10:44–48; 19:1–6), underlining both the normative pattern and the Spirit's sovereign freedom.
Verse 39 — "The promise is to you and to your children, and to all who are far off" Peter now widens the horizon dramatically. "Your children" extends the promise to future generations — a phrase that the Church Fathers and the Council of Trent cite in defense of infant baptism, since the promise is not limited to those capable of adult decision. "Those who are far off" (τοῖς εἰς μακράν) echoes Isaiah 57:19, where God promises peace "to those far and near," and anticipates the mission to the Gentiles — a horizon already implicit at Pentecost through the many nations represented (Acts 2:5–11). The phrase "as many as the Lord our God will call" anchors the universality of the mission in divine initiative: God's call precedes and enables human response.
From a Catholic perspective, Acts 2:37–41 is nothing less than the first formal exercise of the Church's sacramental mission. Several points of specific Catholic teaching crystallize here.
Baptismal regeneration. The Catechism of the Catholic Church teaches unequivocally that "Baptism is the sacrament of regeneration through water and in the word" (CCC 1213) and that it effects "forgiveness of sins" (CCC 977). Peter's words in verse 38 — "be baptized … for the forgiveness of sins" — are among the primary Scriptural foundations for this dogma, cited explicitly at the Council of Trent (Session VII, Canon 2 on Baptism).
The sacramental structure of initiation. The sequence of repentance → baptism → reception of the Holy Spirit prefigures what would develop into the three Sacraments of Initiation: Baptism, Confirmation, and the Eucharist (which appears immediately in Acts 2:42). St. Cyril of Jerusalem, in his Mystagogical Catecheses, treats this Pentecost event as the paradigmatic pattern for Christian initiation.
Infant baptism. St. Augustine and the Council of Carthage (418 AD) drew on verse 39 ("to your children") to support the ancient practice of baptizing infants, insisting that the promise is covenantal and generational, not contingent on adult decision alone. The CCC affirms that "the Church and the parents would deny a child the priceless grace of becoming a child of God were they not to confer Baptism shortly after birth" (CCC 1250).
The ecclesial dimension. St. John Chrysostom, in his Homilies on Acts, notes that those baptized are immediately "added" (προσετέθησαν) to the community — they are not isolated converts but incorporated members of the Body. This is why the CCC speaks of Baptism as "the door which gives access to the other sacraments" (CCC 1213) and the foundation of the Church's communion.
The three thousand baptized at Pentecost were not spiritual seekers who stumbled upon a truth; they were people "cut to the heart" who acted on that conviction immediately and publicly. For Catholic readers today, this passage challenges two opposite temptations: the temptation to reduce faith to private feeling (the interior compunction without the public sacramental response), and the temptation to treat baptism as a social ritual emptied of the expectation of real repentance and Spirit-reception.
Parish RCIA directors and sponsors might ask: Do our candidates experience anything like being "cut to the heart" before they enter the font? For Catholics already baptized, the passage invites a renewed examination of whether the gift of the Holy Spirit received at Baptism and Confirmation is being actively claimed and lived. Peter's call to "save yourselves from this crooked generation" is startlingly contemporary — every generation has its own version of crooked cultural currents from which baptismal identity calls us to stand apart. Finally, the sheer number — three thousand in a day — should stoke missionary imagination: the Church is not meant to be a maintenance institution but a community of perpetual Pentecost.
Verse 40 — "Save yourselves from this crooked generation" Luke's summary note ("with many other words") signals a longer discourse condensed here. "Crooked generation" (γενεᾶς τῆς σκολιᾶς) echoes Deuteronomy 32:5 and Psalm 78:8 (LXX), where Israel's unfaithfulness is described in identical terms. Peter is placing his hearers before an urgent, binary choice: they stand at the junction of the old age of disobedience and the new age of salvation. The imperative "save yourselves" is not Pelagian; in context, the means of salvation has just been specified — repentance and baptism — and the call is to avail oneself of what God has provided.
Verse 41 — "About three thousand souls" The baptism of three thousand in a single day is a harvest of eschatological proportions. Luke uses ψυχαί (souls) — a term recalling the Old Testament way of counting persons (cf. Gen 46:27; Exod 1:5 LXX), subtly evoking the new exodus. Typologically, the contrast with Sinai is unmistakable: at the giving of the Law, three thousand Israelites died for idolatry (Exod 32:28); at the giving of the Spirit, three thousand receive life. The Law kills; the Spirit gives life (cf. 2 Cor 3:6).