Christ’s disciples obeyed his command to remain in Jerusalem until he sent them the Holy Spirit and formed his spiritual body. Acts 2 records the amazing event that occurred on the Day of Pentecost—the Holy Spirit descended upon them, attested by visible and audible signs, forming the church and empowering them to accomplish the mission Christ had given them. Jesus had promised his disciples that he would sent the Holy Spirit for two purposes: First, he promised that he would baptize them with the Holy Spirit (Acts 1:5). Paul later explained what happens when Christ baptizes believers with the Holy Spirit: “For with one Spirit we were all baptized into one body” (1 Cor 12:13)—Spirit baptism unifies all Christians into the body of Christ, the church. Second, he promised that the Spirit would give them special ability to witness of him “in Jerusalem and in all Judea and Samaria, and to the end of the earth” (Acts 1:8), and that is exactly what began to happen. On that day, Peter preached a powerful message of judgment and salvation, admonishing the people gathered there to repent and call upon the name of the Lord.
Thousands became convicted by Peter’s sermon: “So those who received his word were baptized, and there were added that day about three thousand souls” (Acts 2:41). Repentance and faith made these people part of Christ’s spiritual body, for which water baptism served as a visible sign. This act identified these new believers as followers of Christ and allowed them to be added to the number of those who were members of the church.
The book of Acts provides the first glimpse of what worship in the newly formed church consisted. Acts 2:42, immediately following Peter’s Pentecost sermon, succinctly describes the core of this gathered assembly of believers. Luke recounts four commitments to which these believers “devoted themselves.” The first commitment of this infant church was devotion to apostolic teaching. Jesus had promised his disciples that one benefit of the Holy Spirit’s coming was that he would “guide [them] into all the truth” about Christ—he would “take what is [Christ’s] and declare it to [them]” (John 16:13–14). In other words, the Holy Spirit led the apostles to understand the truth about Jesus, and they passed it on to others. They instructed these new believers in the teachings of Jesus, how he had fulfilled Old Testament prophesies, and how they should live with each other and be witnesses for Christ. In the course of time, the apostles wrote down this teaching under the inspiration of the Holy Spirit, which became the writings of the New Testament (2 Tim 3:16, 2 Pet 1:21).
Next, Luke says that these new believers were devoted to “the fellowship”—literally, “communion” (koinonia). These people had a common faith in Jesus Christ and thus a unique fellowship with him and with each other that Jesus had prayed for in his High Priestly Prayer. As the rest of Acts illustrates, this spurred them on to encourage and strengthen one another in that faith, bearing up each other’s burdens, and admonishing one another in the things of the Lord. As the author of Hebrews later indicates, this is a key purpose for gathering as the church—“to stir up one another to love and good works, not neglecting to meet together, as is the habit of some, but encouraging one another, and all the more as you see the Day drawing near” (Heb 10:24–25).
The third commitment of the gathered church was devotion to “the breaking of bread.” The definite article, “the,” indicates that this is specifically speaking about the Lord’s Supper. Jesus, through his apostles, had commanded his people to regularly observe this meal as an expression of their communion with God and with the body of Christ through the shed blood and broken body of Christ (1 Cor 10:16–17). Gatherings of the early church were so characterized by observing this sacred meal that a worship service was simply described as “gathered together to break bread” (Acts 20:7). Participation in the Lord’s Table is, according to Paul, participation with the sacrifice of Christ, and as believers share together and partake of the one bread and the one cup, they demonstrate together their communion with God and each other through Christ. Jesus, through Paul, commanded that believers observe this meal “in remembrance of” him (1 Cor 11:24, 25), thereby proclaiming his death until he comes again (v. 26). Just as with the Passover memorial, this new ordinance is an active reenactment of the death of Christ on behalf of his people such that they are formed by the act.
The fourth commitment Luke lists of this infant church is devotion to public prayer. Again, there is a definite article, “the,” in front of “prayers,” which has at least two implications. First, this is describing more than simply individual, private prayer. Private prayer is important, but these believers were devoted to “the prayers,” meaning public times of prayer together. The other implication is that “the prayers” likely refers to specific prayers that were part of Jewish liturgy. Since every member of this infant church was a Jew, they would have naturally continued using practices from Jewish worship, likely those from their regular synagogue services printed in the previous chapter. In other words, this devotion implies that this early church was devoted to regularly meeting for corporate worship, and these corporate gatherings were so characterized by prayer–—by dialogue with God—that they could be called “the prayers.”
The rest of the book of Acts demonstrates continued devotion to these commitments. The earliest Jewish Christians continued to worship in the temple (5:42) and in synagogues (15:21). Christians gathered for the express purpose of worship (13:2), and church leaders taught and preached the word of the Lord regularly (15:35), baptizing new converts and adding them to the church. Over time, the first day of the week became a significant day for worship, eventually replacing the Sabbath, since it was the day on which Christ rose from the dead (20:7).