What does Matthew 16:15 mean?

Different groups in Jesus' era held their own opinions on the concept of a Messiah, or a Promised One. Jesus has asked His disciples about the people's view of "the son of man," which His disciples understand as a reference to Jesus Himself. This question might have been aimed at those following Him around Galilee to hear Him preach and see His miracles. Luke's details from this conversation include Jesus asking, "Who do the crowds say that I am" (Luke 9:18)?

According to the disciples, there are a few common opinions. Some think Jesus is one of the prophets of old, returned in the fulfilment of prophecy. Others think Him to be John the Baptist resurrected—despite that Jesus and John lived at the same time and were about the same age. John had recently been executed by Herod Antipas (Matthew 14:1–12).

Yet, the opinion of the crowd is not really the point of Jesus' question. He seems to have asked only to set up the idea found in this verse. This pointedly separates popular opinion from personal belief: the emphasis is on this group, not the overall public. Who do these closest followers think Jesus is?

This is a key moment in Matthew's narrative. Until Jesus' core followers truly understood His identity, they would not truly understand the gospel. Once they fully knew who He was, they could begin to represent Him to the world (John 16:12–15). Peter's response in the following verse reveals He understands who Jesus is (Matthew 16:16–17), though almost immediately he will also reveal the limits of his understanding (Matthew 16:21–23).