In the preceding verses the Lord lays down the character of such as belong to the kingdom of the heavens. Now He states their position here below. Is it truly applicable to you? Do you in unbelief treat it as impracticable or indifferent?
If I own myself a lost sinner, and in me, that is in my flesh, no good thing dwells, neither salt nor light is mine, but sin dwells in me. It would be sheer presumption to claim that I am born either the one or the other. Naturally I am corrupt, and as to God and His things dark as night. Important as baptism is, it in no case according to scripture produces so mighty a change; but life in Christ does, which the believer receives through the Spirit and the word of God. As its fullness and perfection were in the Son, so of His fullness did all we receive, and grace for grace. It is no presumption to believe God, nor what He declares He gives to those who receive Christ.
Let me beseech you, fellow-believer, not to slur over nor shirk the position in which the Lord sets you here below. These are His words— “Ye are the salt of the earth; but if the salt have lost its savor, wherewith shall it be salted? It is thenceforth good for nothing save to be cast out and to be trodden down by men. Ye are the light of the world: a city set on a hill cannot be hid. Nor do they light a lamp, and put it under the bushel but upon the stand, and it shineth for all that are in the house. Thus let your light shine before men, that they may see your comely works, and glorify your Father that is in the heavens.” Let us earnestly seek to make this good, instead of slipping it through or shoving it on to a Jewish remnant.
As there were two broad characteristics among the foregoing “blessed,” righteousness and grace, both displayed in Christ and in Christianity, so is it with the position of the disciples. In vers. 3 to 6 are the righteous characters: in 7 to 9 the gracious: followed by the blessing of the persecuted for righteousness' sake in 10, and by those persecuted yet worse for Christ (i.e. grace) in 11, and their joy, exultation, and reward above in 12. The position too is presented accordingly. In ver. 13 we have the righteous side; in 14 and the rest the side of grace, but both to be verified in our practice.
Salt is the righteously preservative principle. It is sharp rather than sweet, but guards from impurity and decomposition. It gives fixity to what is good and wholesome. It proves all things, and holds fast the right. It keeps aloof from every form of wickedness. When then the disciples are called the salt of the earth, the Lord designates them as set apart to God the Father, and in patient continuance of good work seeking for glory and honor and incorruptibility at Christ's coming. They obey the truth, and are to hold fast what they have till then. If they lose the good savor, it is fatal. Saltless salt (and such a change was familiar in those lands) cannot be restored. It is not fit for anything but to be trodden down on the streets, as it often was.
How has it fared with the holy deposit in Christendom? Has the salt there retained its virtue? Did the favored Gentile abide in goodness, any more than the Jew under law? If not, cutting off is the sentence of God (Rom. 11:21, 2221For if God spared not the natural branches, take heed lest he also spare not thee. 22Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off. (Romans 11:21‑22)). All the more should every faithful soul humble himself, repent, and look to the Lord who is as willing as He is able to make Him stand.
But are we not responsible as “the light of the world”? If it is not the property or power of salt to cure corruption, it is for light to illuminate the dark. It goes out and around. And we may notice it is to “the world” at large here in this appropriate diffusion by grace, as the salt is “of the earth,” the ordered scene of privileges. As being the light, it is compared to a city set on a hill and not to be hid; and not this only, but as penetrating the home, it is as a lamp (not absurdly under the bushel as its extinguisher, but) upon its stand, that all in the house may enjoy its brightness.
Only let us not forget the Lord's momentous caution as to this. “Thus let your light (your living profession of Him, Who is the true Light and made you light in Him) shine before men, that they may see (not your inconsistencies, but) your comely works, and glorify your Father that is in the heavens.” He means the very reverse of men displaying their benevolent works before their fellows, so as to bring glory to themselves. He would have His own let their confession of Him, the one source of their light, shine, so that men may see the goodly fruits, and therefore glorify not the disciples but our Father in the heavens, the Father of lights, of whom is every good giving, and whence comes down every perfect gift from above.