Luke identifies historically the Roman rulers: Tiberius Caesar, Herod, Pontius Pilate, and others as well as the Jewish high priests. But the main actor in God's story was none of these. It was John the Baptist who preached a baptism of repentance for the forgiveness of sins. Why? It was to prepare the way for the Messiah. Isaiah 40:3-5 foretold John's ministry.
John's message was first of all, "produce fruit in keeping with repentance." We must repent of our sins to welcome Jesus as Messiah. We can't depend on our own heritage or righteousness. We must repent of our greed, materialism, dishonesty, extortion, and false accusations. We must turn from sin and self-seeking and turn to God.
John's greater message was: "I'm nobody; get ready for the Messiah. He's the Judge. He baptizes with the Holy Spirit and fire." John received no reward for his preaching; he was put in prison. His reward, and ours, is from God.
Application: Lord, may my life bear the good fruit of repentance and faith in Jesus. Cleanse all my sins and baptize me with the Holy Spirit and fire.
One Word: Repent; be baptized with the Holy Spirit