Preaching the Kingdom
John was sent ahead of Jesus to announce His approach – to introduce Him (Matthew 3:1-4). John’s introduction was limited to how Jesus fit into the only revelation John had: the law given to the Jews through Moses (Matthew 3:7-17).
His revelation did not include what the coming Kingdom would look like, so he apparently expected it to look like what the Pharisees expected – perfect obedience to the law. The difference would be that the Pharisees imagined themselves beating everyone into submission to the law, and John imagined Jesus beating everyone into submission to the law.
When John was in prison for his ministry to Herod regarding Herodias, he began to hear reports of the works Jesus was doing. The reports did not sound like what he expected. They were so different, in fact, that he sent some of his disciples to ask Jesus if he had made a mistake by introducing Him as Messiah. The answer Jesus sent him pointed to His miracles and His preaching as reasons to believe He was Messiah. Then John was killed.
Jesus then recruited servants who could continue to go ahead of Him to announce His approach and introduce Him as King. These were receiving revelation of the Kingdom. Somehow, even the least of these were more effective in their ministries than John the Baptist was (Luke 7:28). He sent them out with instructions that included praying that the Lord of the harvest would send laborers into His harvest (Luke 10:1-12). (That section is very important to read).
They were not preaching church membership. They were not handing out indulgences to protect sinners from the lake of fire. They were preaching the Kingdom. They were manifesting the Kingdom. They were doing the new version of the job John the Baptist had been doing, only they were doing the same things Jesus had been doing so His introduction matched His appearance. We are called to preach and manifest the Kingdom, too.
That doesn’t mean we are not to also preach Jesus as Savior, though. It adds to that invitation an invitation to live a life of service to Jesus as King. It gives purpose to the life we live before our flesh dies. It gives us opportunities to be faithful in responsibility, and therefore rewarded in authority (Luke 19:11-27).