And when He (the Comforter) has come, He will reprove the world of sin.” John 16:8.
This is the great office of the Spirit- this is His first work, prior to His bringing the soul to rest on the great sacrifice for sin. Not a step will the soul take to Christ, until that soul has been brought in guilty and condemned by the law of God. And this is the work of the Spirit. “No man,” says the excellent Newton, “ever did or ever will feel himself to be a lost, miserable, and hateful sinner, unless he is powerfully and supernaturally convinced by the Spirit of God.”
And what is the instrument by which the Spirit thus powerfully and supernaturally convinces of sin? We reply, the Law. “By the law is the knowledge of sin.” “The law was our schoolmaster to bring us unto Christ.” The law, brought into the conscience by the Holy Spirit; condemns the man, and leads him to condemn himself; it holds up to view the holiness of God- the purity and inflexibility of every precept- contrasts it with the unrighteousness, guilt, and misery, of the sinner, and thus prostrates the soul in the dust, exclaiming in all the lowliness of self-accusation, “the law is holy, just, and good- I am guilty, guilty, guilty.” Through this instrument- the law of God- and thus effectually, does the Holy Spirit convince the soul of sin, and lay it low before God.