Repentance is everything. Are there worshippers who have never repented truly of your sin? You haven’t come to Christ and acknowledged that you deserve eternal condemnation and judgment. You have never come to him and acknowledge that only by what Christ has done can your sin be taken away. You can contribute nothing! You have no goodness, no power to secure favour from God, apart from what Christ has done on your behalf, in taking your burden of guilt and sin and receiving your punishment in your place. Have you, with all that in mind, kneeled before the Lord and acknowledged your faults, failings, and fallen heart, your selfishness and pride, holding nothing back, with shame telling him your desperate need of forgiveness and love and new life? That is what we are to preach – repentance. There is no way into the kingdom of God without that.
How much did the disciples at this point actually know about the message of salvation? We know that they did not fully grasp the atoning death of Christ until afterwards. They did not yet clearly see the method by which sin would be removed. But some people ask, ‘What did they know? How much did they understand?’ Well, quite a lot. At this point it is one year and nine months, or thereabouts, after they have been under the instruction of Jesus Christ, and this point (and the death of John the Baptist, which is referred to in subsequent verses) was somewhere between, John’s Gospel chapter 5 and chapter 7. Everything up to chapter 5 in John’s Gospel had occurred before this point, and also the Sermon on the Mount had been delivered. That helps a great deal; it tells us a lot. The disciples had been baptising people, who repented of their sin on behalf of Jesus Christ in great numbers, even more than John the Baptist himself. They did the baptisms.
What Christ said to Nicodemus about the necessity of the new birth, how he preached to him and dealt with him, John 3.16; all these things came before this point and so it gives you an insight into how much the disciples were able to preach and to say. So they did preach the necessity of repentance, that God would show mercy to those who repented, that Messiah had come, he would show all things himself and exactly how it would be done. He was bringing in his kingdom, his new order, his new church and we could turn to passages like John 5. You can see that to the disciples repentance meant the new birth. They were preaching so that God would change people’s nature; bring them into the kingdom. This is why there was so much hostility. They weren’t yet clear on Calvary, the means of atonement, but they were very clear on the need for repentance and trust in the mercy of God.