Mark 1:14
. Preaching the Gospel of the kingdom of God. Matthew appears to differ a little from the other two: for, after mentioning that Jesus left his own city Nazareth, and departed to Capernaum, he says: from that time Jesus began to preach. Luke and Mark, again, relate, that he taught publicly in his own country. But the solution is easy; for the words which Matthew employs, ἀπὸ τότε, from that time, ought to be viewed as referring, not to what immediately precedes, but to the whole course of the narrative. Christ, therefore, entered into the exercise of his office, when he arrived at Galilee. The summary of doctrine which is given by Matthew is not at all different from what, we have lately seen, was taught by John: for it consists of two parts, — repentance, and the announcement of grace and salvation. He exhorts the Jews to conversion, because the kingdom of God is at hand: that is, because God undertakes to govern his people, which is true and perfect happiness. The language of Mark is a little different, The kingdom of God is at hand: repent ye, and believe the Gospel But the meaning is the same: for, having first spoken of the restoration of the kingdom of God among the Jews, he exhorts them to repentance and faith.
But it may be asked, since repentance depends on the Gospel, why does Mark separate it from the doctrine of the Gospel? Two reasons may be assigned. God sometimes invites us to repentance, when nothing more is meant, than that we ought to change our life for the better. He afterwards shows, that conversion and “newness of life” (Romans 6:4) are the gift of God. This is intended to inform us, that not only is our duty enjoined on us, but the grace and power of obedience are, at the same time, offered. If we understand in this way the preaching of John about repentance, the meaning will be:” The Lord commands you to turn to himself; but as you cannot accomplish this by your own endeavors, he promises the Spirit of regeneration, and therefore you must receive this grace by faith.” At the same time, the faith, which he enjoins men to give to the Gospel, ought not, by any means, to be confined to the gift of renewal, but relates chiefly to the forgiveness of sins. For John connects repentance with faith, because God reconciles us to himself in such a manner, that we serve him as a Father in holiness and righteousness.
Besides, there is no absurdity in saying, that to believe the Gospel is the same thing as to embrace a free righteousness: for that special relation, between faith and the forgiveness of sins, is often mentioned in Scripture; as, for example, when it teaches, that we are justified by faith, (Romans 5:1.) In which soever of these two ways you choose to explain this passage, it still remains a settled principle, that God offers to us a free salvation, in order that we may turn to him, and live to righteousness. Accordingly, when he promises to us mercy, he calls us to deny the flesh. We must observe the designation which Paul gives to the Gospel, the kingdom of God: for hence we learn, that by the preaching of the Gospel the kingdom of God is set up and established among men, and that in no other way does God reign among men. Hence it is also evident, how wretched the condition of men is without the Gospel.