World Wide Study Bible
a Bible passage
49. Thou art the Son of God. That he acknowledges him to be the Son of God from his divine power is not wonderful; but on what ground does he call him King of Israel? for the two things do not appear to be necessarily connected. But Nathanael takes a loftier view. He had already heard that he is the Messiah, and to this doctrine he adds the confirmation which had been given him. He holds also another principle, that the Son of God will not come without exercising the office of King over the people of God. Justly, therefore, does he acknowledge that he who is the Son of God is also King of Israel And, indeed, faith ought not to be fixed on the essence of Christ alone, (so to speak,) but ought to attend to his power and office; for it would be of little advantage to know who Christ is, if this second point were not added, what he wishes to be towards us, and for what purpose the Father sent him. The reason why the Papists have nothing more than a shadow of Christ is, that they have been careful to look at his mere essence, but have disregarded his kingdom, which consists in the power to save.
Again, when Nathanael calls him King of Israel, though his kingdom extends to the remotest bounds of the earth, the confession is limited to the measure of faith. For he had not yet advanced so far as to know that Christ was appointed to be King over the whole world, or rather, that from every quarter would be collected the children of Abraham, so that the whole world would be the Israel of God. We to whom the wide extent of Christ’s kingdom has been revealed ought to go beyond those narrow limits. Yet following the example of Nathanael, let us exercise our faith in hearing the word, and let us strengthen it by all the means that are in our power; and let it not remain buried, but break out into confession.