What did the Jewish people Peter addressed have to recognize about Jesus?
The Jewish people Peter addressed had to recognize that Jesus was the Christ, and only Jesus. Scripture declares there is no other name under heaven given among men by which we must be saved, so salvation is found in no one else. This narrow truth applied directly to Peter's Jewish audience.
Les explains that Peter is speaking to the Jewish covenant people and that verse 12 is critical: there is no other name under heaven given among men whereby we must be saved. This still spills over into our Gospel. Les points out that many sincere people follow a cult leader, Buddha, Muhammad, or whatever, but this verse is narrow and brings it down to only one way. For the Jew at that particular time Peter was dealing with, they had to recognize that Jesus was the Christ, and only Jesus. Les notes that modern Jews, especially Orthodox, often refuse to admit Jews ever followed Christ, but thousands did early on, and archaeology is proving many Jews embraced Christ as their Messiah and Redeemer. The vast majority rejected it, and God went to the Gentile without them, but at this point Peter is still dealing with the covenant people.
Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved.