Matthew 16:13-20
In this passage in Matthew, Jesus asks his disciples "Who do men say that I, the Son of Man am?" After they respond, he then asks them personally "But who do you say that I am?" This is a question that we all have to answer in this life. There are all kinds of opinions out there about who Jesus is, but only one opinion is fit for the citizens of the Kingdom of Heaven. Jesus is the Messiah, the Son of the Living God, and those that wish to enter the Kingdom of Heaven must own Him as so.
Jesus then strictly commanded His disciples not to go out and tell anyone that He was the Christ. They had an understanding that He was the Messiah, but in the verses to come its clear that they didn't understand what the Work of the Messiah would be. Had they gone out and proclaimed Him as the Messiah, they would have proclaimed a cross-less Messiah.