What does Acts 2:21 mean?
In this first sermon of the Christian church, Peter sets the standard for sharing the gospel with Jews. Around 900,000 Jews from around the Roman Empire have come to Jerusalem to celebrate Pentecost. Although they all probably speak Greek or Aramaic, most were raised speaking a minor, regional dialect. A crowd of these travelers has come upon a group of Galileans who seem to know every one of those dialects. Peter uses Old Testament prophecy—their own Scriptures—to explain what is happening. As Joel promised, the Holy Spirit has come upon the servants of God, giving them the ability to prophecy, or reveal truth (Acts 2:17–18). Now, Peter starts to show how this prophecy relates to Jesus.This verse quotes Joel 2:32. Joel 2:28–31 describes how those who repent will be given the Holy Spirit and special messages from God while those who continue to reject God will see blood, fire, smoke, and a darkened sky. There are two distinct groups, and whoever calls on the Lord will be saved.
Those who watched Jesus die on the cross witnessed this recently. One of the thieves who hanged with Him trusted Jesus with his eternal soul. With no other work or admission, Jesus assured him he would go to paradise (Luke 23:39–43). Now Peter's job is to show how "the Lord" is not a hoped-for Messiah who will arrive in the future, but Jesus of Nazareth who was murdered fifty days before and rose again. For that, Peter will transition from the words of Joel to the words of David (Acts 2:25–35).
"Name" is from the Greek root word onoma. It encompasses more than what someone is called. This idea includes all thoughts, feelings, and images that come to mind when thinking of the person. The "name of the Lord" includes Jesus' character, sovereignty, authority, power, and deity. To call on or pray in Jesus' name is to place our needs in the hands of the God of the universe.
Acts 2:14–36 transcribes the first sermon ever given by a Christian. The Holy Spirit that Jesus promised (John 14:16–17) has come upon 120 of His followers in Jerusalem (Acts 1:15; 2:1–4). They immediately start speaking in different languages, shocking a crowd of Jews and proselytes who are in town to celebrate Pentecost (Acts 2:5–11). Some of the crowd dismiss the speech as nonsense; others are very interested (Acts 2:12–13). Peter, combining his natural enthusiasm as spokesman for the group with wisdom from the Spirit, responds by obeying Jesus and being His witness (Acts 1:8).
Acts 2 describes the beginning of the church in three episodes. First, the Holy Spirit comes upon the Jesus-followers in Jerusalem, equipping them with the ability to teach the gospel in different languages (Acts 2:1–13). Second, Peter gives a public declaration using Old Testament prophecy to show Jesus is the long-awaited Jewish Messiah (Acts 2:14–36). Third, people believe. They repent, trust Jesus will forgive their sins, and agree to be baptized as a public sign that they are now Jesus-followers (Acts 2:37–47). That quickly, the church is born.
