The first coming of Jesus was prophesied and recorded as a testimony of God and His promises of His Word.  People who were waiting and looking for the return of Jesus admired Him.  People knew of His coming prior to His birth, at the time of His birth, and after His birth.

John the Baptist was the one who fulfilled prophecy of the beginning ministry of Jesus.  Just as the establishment knew of the arrival of the King, they also were given the announcement of the beginning of the Messiah’s ministry and the beginning of the foundation of the Kingdom of God.  John was announcer to the establishment of the beginning of the Kingdom of God and the ministry of Jesus