There are two words in the New Testament translated repentance -- one of which denotes a change of mind, or a reformation of life; and the other, sorrow or regret that sin has been committed. The word used here is the former; calling the Jews to a change of life, or a reformation of conduct. In the time of John, the nation had become extremely wicked and corrupt, perhaps more so than at any preceding period, Hence both he and Christ began their ministry by calling to repentance.
The kingdom of heaven is at hand. The phrases, kingdom of heaven, kingdom of Christ, and kingdom of God, are of frequent occurrence in the Bible. They all refer to the same thing. The expectation of such a kingdom was taken from the Old Testament, and especially from Daniel, Da 7:13,14. The prophets had told of a successor to David that should sit on his throne, 1 Ki 2:4; 8:25; Jer 33:17.
The Jews expected a great national deliverer. They supposed that when the Messiah should appear, all the dead would be raised; that the judgment would take place; and that the enemies of the Jews would be destroyed, and themselves advanced to great national dignity and honour.
The language in which they were accustomed to describe this event was retained by our Saviour and his apostles. Yet they early attempted to correct the common notions respecting his reign. This was one design, doubtless, of John in preaching repentance. Instead of summoning them to military exercises, and collecting an army, which would have been in accordance with their expectations, he called them to a change of life; to the doctrine of repentance -- a state of things far more accordant with the approach of a kingdom of purity.
The phrases, kingdom of God and kingdom of heaven, have been supposed to have a considerable variety of meaning. Some have thought that they refer to the state of things in heaven; others, to the personal reign of Christ on earth; others, that they mean the church, or the reign of Christ in the hearts of his people. There can be no doubt that there is reference in the words to the condition of things in heaven, after this life. But the church of God is a preparatory state to that beyond the grave; a state in which Christ pre-eminently rules and reigns; and there is no doubt that it sometimes refers to the state of things in the church; and it means, therefore, the state of things which the Messiah was to set up -- his spiritual reign began in the church on earth, and completed in heaven.
The phrase would be best translated, "the reign of God draws near." We do not say commonly of a kingdom that it is moveable, or that it approaches. A reign may be said to be at hand; or the time when Christ should reign was at hand. In this sense it is meant that the time when Christ should reign, or set up his kingdom, or begin his dominion on earth, under the Christian economy, was about to commence. The phrase, then, should not be confined to any period of that reign, but includes his whole dominion over his people on earth and in heaven.
In the passage here it clearly means that the coming of the Messiah was near; or that the time of the reign of God, which the Jews had expected, was coming.
The word heaven, or heavens, as it is in the original, means sometimes the place, so called; and sometimes is, by a figure of speech, put for the Great Being whose residence is there; as in Da 4:26, "the heavens do rule." See also Mr 11:30; Lu 15:18. As that kingdom was one of purity, it was proper that the people should prepare themselves for it by turning from their sins, and directing their minds to a suitable fitness for his reign.