So, too, before man’s reason, wherein is mortal sin, is restored by justifying grace, he can avoid each mortal sin, and for a time, since it is not necessary that he should be always actually sinning.  But it cannot be that he remains for a long time without mortal sin.  Hence Gregory says (Super Ezech.  Hom. xi) that “a sin not at once taken away by repentance, by its weight drags us down to other sins”:  and this because, as the lower appetite ought to be subject to the reason, so should the reason be subject to God, and should place in Him the end of its will.  Now it is by the end that all human acts ought to be regulated, even as it is by the judgment of the reason that the movements of the lower appetite should be regulated.  And thus, even as inordinate movements of the sensitive appetite cannot help occurring since the lower appetite is not subject to reason, so likewise, since man’s reason is not entirely subject to God, the consequence is that many disorders occur in the reason.  For when man’s heart is not so fixed on God as to be unwilling to be parted from Him for the sake of finding any good or avoiding any evil, many things happen for the achieving or avoiding of which a man strays from God and breaks His commandments, and thus sins mortally:  especially since, when surprised, a man acts according to his preconceived end and his pre-existing habits, as the Philosopher says (Ethic. iii); although with premeditation of his reason a man may do something outside the order of his preconceived end and the inclination of his habit.  But because a man cannot always have this premeditation, it cannot help occurring that he acts in accordance with his will turned aside from God, unless, by grace, he is quickly brought back to the due order.

Reply Obj. 1:  Man can avoid each but not every act of sin, except by grace, as stated above.  Nevertheless, since it is by his own shortcoming that he does not prepare himself to have grace, the fact that he cannot avoid sin without grace does not excuse him from sin.

Reply Obj. 2:  Correction is useful “in order that out of the sorrow of correction may spring the wish to be regenerate; if indeed he who is corrected is a son of promise, in such sort that whilst the noise of correction is outwardly resounding and punishing, God by hidden inspirations is inwardly causing to will,” as Augustine says (De Corr. et Gratia vi).  Correction is therefore necessary, from the fact that man’s will is required in order to abstain from sin; yet it is not sufficient without God’s help.  Hence it is written (Eccles. 7:14):  “Consider the works of God that no man can correct whom He hath despised.”

Reply Obj. 3:  As Augustine says (Hypognosticon iii [Among the spurious works of St. Augustine]), this saying is to be understood of man in the state of perfect nature, when as yet he was not a slave of sin.  Hence he was able to sin and not to sin.  Now, too, whatever a man wills, is given to him; but his willing good, he has by God’s assistance. ________________________