4:12-17 It is just with God to take the gospel and the means of grace, from those that slight them and thrust them away. Christ will not stay long where he is not welcome. Those who are without Christ, are in the dark. They were sitting in this condition, a contented posture; they chose it rather than light; they were willingly ignorant. When the gospel comes, light comes; when it comes to any place, when it comes to any soul, it makes day there. Light discovers and directs; so does the gospel. The doctrine of repentance is right gospel doctrine. Not only the austere John Baptist, but the gracious Jesus, preached repentance. There is still the same reason to do so. The kingdom of heaven was not reckoned to be fully come, till the pouring out of the Holy Spirit after Christ's ascension.
17. From that time Jesus began to preach, and to say, Repent; for the kingdom of heaven is at hand—Thus did our Lord not only take up the strain, but give forth the identical summons of His honored forerunner. Our Lord sometimes speaks of the new kingdom as already come—in His own Person and ministry; but the economy of it was only "at hand" until the blood of the cross was shed, and the Spirit on the day of Pentecost opened the fountain for sin and for uncleanness to the world at large.
Calling of Peter and Andrew James and John (Mt 4:18-22).