What does Acts 2:14 mean?
Depending on what version is used, and how one counts, the Bible contains somewhere around thirty-five instances of the phrase "Peter said" or "Peter answered"—most of those in the Gospels. Some of his statements were requests for clarification (Matthew 15:15; Luke 12:41). Some were because he was so overwhelmed he didn't know what to do (Matthew 17:4). Some were rash vows he couldn't keep (John 13:37). Other words were inspired (John 6:68). Once he receives the Holy Spirit, Peter's natural tendency to speak up is transformed, and he becomes a powerful witness for Jesus.In the book of Acts, Peter gives five speeches of varying lengths. Three are evangelistic (Acts 2:14–41; 3:12–26; 10:34–43) and two are explanatory (Acts 4:8–12; 11:4–17). He gave many more over the course of his life, but these are representative enough to show a common thread. All of Peter's speeches start with what is going on in that moment and explain it in the context of Jesus is the Savior. In Acts 3, he addresses a crowd that is amazed when he heals a lame man (Acts 3:1–10), saying the power by which the man is healed is given by Jesus, whom they crucified. In Acts 10, he defends his presence in the house of Cornelius, a Gentile centurion who wanted to know how he could be saved.
Here, Peter will explain why it is all these Jews can understand the disciples' speech in their own language. It is the fulfillment of a prophecy by the prophet Joel (Acts 2:16–21).
The wording Peter uses is somewhat poetic. Luke explains that Peter "lifted his voice" and "addressed them," which both mean the same thing, but the repeat adds a bit of a lilt to the phrasing. Similarly, Peter's use of the phrases "Men of Judea" and "all who dwell in Jerusalem" and then "let this be known to you" and "give ear to my words" follow the Hebrew poetic form of synthetic parallelism which is so common in the books of Psalms and Proverbs. That Peter is speaking in such a lyrical way is probably one of the reasons the high priests are amazed at the "uneducated, common" fishermen from Galilee (Acts 4:13).