Sinfullness of Unbelief
The reason why persons who appear to be in some measure, convinced of sin, so often lose their convictions; and why so many professors of religion fall away and disgrace their profession, is, because the work of conviction was never thoroughly performed; because they were never convinced of unbelief. They saw, perhaps, that they were sinners. They felt convinced of many sins in their tempers and conduct; they in some measure corrected and laid aide these sins; then their consciences ceased to reproach them, and they flattered themselves that they had become new creatures. But, meanwhile, they knew nothing of the great sin of unbelief, and therefore never confessed, repented of, or forsook it, until it proved their destruction. They were like a man who should go to a physician to be healed of some slight external wound, while he knew nothing of a deep-rooted disease which was preying upon his vitals. Professors, try yourselves by these remarks. Look back to the time when you imagined yourselves to be convinced of sin, and say whether you were then convinced, or whether you have at any time since been convinced of the exceeding sinfulness of unbelief. If not, there is great reason to fear that you are deceived, that you have mistaken the form for the power of godliness.
It is God’s invariable method to humble before he exalts; to show us our diseases before he heals them; to convince us that we are sinners before he pronounces our pardon. When, therefore, the Spirit of all grace and consolation comes to comfort and sanctify a sinner, he begins by acting the part of a reprover, and thus convincing him of sin. The sin of which he more particularly aims to convince him is unbelief. He shall reprove the world of sin, says our Saviour. Why? Because they are murderers, thieves, or adulterers? No. Because they are guilty of slander, fraud, or extortion? No. Because they are intemperate; dissipated, or sensual? No. Because they are envious, malicious, or revengeful? No; but because they are unbelievers, because they believe not on me.
If there is one fact, or doctrine, or promise in the Bible, which has produced no practical effect upon your temper or conduct, be assured that you do not truly believe it.