J. N. Darby

335 All through this conflict, what is the standard of the path of the saint who has got this hope (v. 12)? why talk of falling? - "lest any man fall after the same example of unbelief," v. 11. Because the constant tendency of the flesh in the saint is to that to which it will bring the unrenewed professor, and would bring us, were we not kept of God. It is the working of my will. I get away from the strength of God, and therefore this allusion to the falling in the wilderness. How does God work in this? He sends His word, which detects the things which lead to falling. "For the word of God is quick and powerful, and sharper than any two-edged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart." The word is the light which shews him that which is in his heart, which would tend to this fall. The thing which produces the danger is detected by the searching light of the word (v. 12). NOW it is that the soul does not shrink from the light; but, as in Psalm 139, says, "Search me, O God." But O, what confidence that is, what amazing confidence! Is there anything that can prove such confidence in grace as that? Could any, who thought God would impute the sin, say, "See if there be any way of wickedness within me"? The moment he knows that God has wrought salvation and quickened him in the grace of Christ, he can say that.