Sincerity does not guarantee we will not ever fall but it helps us up again when we do. The hypocrite, however, lies where he falls until he dies. Thus he is said to “fall into mischief” (Proverbs 24:16). The sincere man stumbles as any traveler might do, but he gets up and resumes his journey with more caution and speed than before. But the hypocrite plunges as a man from the top of a mast who is engulfed past any hope of recovery in the devouring sea.
We see this principle in King Saul’s life. When his false heart discovered itself, he tumbled down the hill and did not stop, but went from one sin to another. In just a few years he had plummeted far from the place where he first left God. Once he had been so ready to worship God that he could not wait for the prophet Samuel to arrive—but later he was so far from seeking God that he went to a witch for council. And in the last act of his bloody tragedy, Saul desperately threw his life into the devil’s mouth by self-murder.
The reason Saul’s sin crushed him to death was that his heart was never right with God in the first place. Samuel hinted at this truth when he told Saul “The Lord sought him a man after his own heart? (1 Samuel 13:14). Of course David himself fell into a sin far worse than Saul’s wickedness—for which God rejected that first king—but the difference was that in David’s life sincerity was the “root of the matter” (Job 19:28).
There is double reason for the recovering strength of sincerity. One stems from the nature of sincerity itself and the other proceeds from God’s promise which settles into the sincere Christian’s soul.
Restoring nature of sincerity itself kindles the soul. Sincerity is to the soul as the soul is to the body, a spark of divine life kindled in man’s heart by the Spirit of God. It is the seed of God remaining in the saint.
—William Gurnall

There is only one way of becoming holy, as God is: and it is the obvious one of opening the entire being to the all pervading presence of the Holy One. None of us can acquire holiness apart from God. It dwells in God alone. Holiness is only possible as much as the soul’s possession of God; no, better still, as God’s possession of the soul. It never can be inherent, or possessed apart from the Divine fullness, any more than a river can flow on if it is cut off from its fountain head. We are holy up to the measure in which we are God-possessed. The least holy man is he who shuts God up to the strictest confinement, and the narrowest limits of His inner being; partitioning Him off from daily life by heavy curtains of neglect and unbelief. He is holier who more carefully denies self, and who seeks a large measure of Divine indwelling. The holiest is the man who yields himself completely to be influenced, swayed, possessed, and inspired by that Spirit who longs to make us the fullest extent partakers of the Divine nature.