Article 13 — Whether someone in a state of grace is able to avoid mortal sin

Thirteenth, it is asked whether someone in a state of grace is able to avoid mortal sin. (Parallel texts: below: a. 14; q. 27, a. 5, ad 3; ST I-II.109.9-10; I-II.137.4; SCG III.155; In II Sent., d. 29, exposition of text; Commentary on the Psalms, Ps 31.)

Obj. 1: It seems not: for no one is bound necessarily to ask from God what one is able to accomplish by one self; but anyone, so long as they possess grace, must necessarily ask from God to be liberated from future sins; hence in 2 Corinthians 13:7 the Apostle says, speaking to the faithful and to the saints, yet let us pray to God that we might do nothing evil; therefore even those possessing grace are unable to avoid sin.

Obj. 2: Furthermore, even those possessing grace must necessarily say the Lord’s prayer; but in that prayer one asks that man might be preserved from sin, according to Cyprian’s exposition, as Augustine narrates in the book On Perseverence; (Augustine, On Perseverence, ch. 2 (PL 45:996).) therefore, one possessing grace cannot avoid mortal sin by himself.

Obj. 3: Furthermore, perseverance is a gift of the Holy Spirit; but to possess the gifts of the Holy Spirit is not even in the power of one possessing grace; therefore, since it pertains to perseverance to abstain from mortal sin even to the end of one’s life, it also seems that one possessing grace cannot avoid mortal sin.

Obj. 4: Furthermore, just as non-being is to the being of nature, so is the defect of sin to the being of grace; but the creature that has received the being of nature from God cannot preserve itself in the being of nature such that it does not fall into non-being, unless it be preserved by the hand of the Creator; (Gregor. [Moral. XVI c. 37 (PL. 75, 1143 C)] ut dicitur infra q. 27 a.3) therefore, also someone who has received grace cannot by himself act such that he does not fall into mortal sin.

On the contrary (1) is what it says in 2 Corinthians 12:9: my grace is sufficient for you; but it would not be sufficient if mortal sin could not be avoided by it; therefore, man can avoid mortal sin by grace.

Furthermore (2) this seems to be the case from the words of the Teacher in the Sentences (Peter Lombard, Sentences, bk. 2, d. 25, ch. 6.) where he says that after the restoration, yet before being fortified, man is pressed upon by concupiscence, though he is not overcome; and he is indeed weak with regard to evil, but he has grace with regard to the good, such that he is able to sin on account of his freedom and weakness, and is able not to sin unto death due to his freedom and assisting grace.

I answer that it must be said that it is one thing to say that one is able to abstain from sin and another to say that one is able to persevere to the end of one’s life in abstinence from sin. For when someone is said to be able to abstain from sin, the ability is brought to bear upon the negation alone, namely, such that someone is able not to sin. Anyone in a state of grace is capable of this, speaking with regard to mortal sin, for there is no habitual inclination toward sin in the one possessing grace; much rather is there in him a habitual inclination to avoid sin. And thus, as soon as something occurs to him under the notion of mortal sin, he disagrees with it from a habitual inclination, unless he should strive to the contrary by following his desires; which are nevertheless not necessary to follow, even though he cannot avoid some motion of desire arising which wholly anticipates the act of free choice.

Thus, since he cannot make it that there be no motion of concupiscence wholly preceding the act of free choice, he is unable to avoid all venial sins; but since there is in him no motion of free choice preceding a full deliberation, and dragging him away toward sin as though by a habitual inclination, thus, he is able to avoid all mortal sins. But when it is said that he is able persevere to the end of his life in abstinence from sin; then "ability" pertains to something affirmative, namely that someone puts themselves in such a state that sin is not able to exist in him; for otherwise man is is not able to make himself persevere by an act of free choice unless he were to make himself unable to sin. But this does not fall within the power of free choice, for the motive power that carries it out does not attain to this. Therefore man is unable to be a cause of perseverance for himself, but it is necessary for him to beg for this perseverance from God.

Reply Obj. 1: To the first it must be said that in this respect the Apostle was praying that they might not commit anything evil, inasmuch as they were unable to persevere in abstinence from evil except with the help of divine assistance.

Reply Obj. 2: One must respond similarly to the second.

Reply Obj. 3: To the third it must be said that perseverance is said in two ways: for it is sometimes a particular virtue, and in this way it is a certain habit whose act is to possess the intention of persevering firmly; and in this way every one who possess grace has perseverance. In another way perseverance is understood inasmuch as it is a certain circumstance of virtue, denoting the virtue's permanence all the way to the end of life; and in this way perseverance is not within the power of the one who possesses grace.

Reply Obj. 4: To the fourth it must be said that just as when we speak of nature we do not exclude that by which nature is preserved in being, so also when we speak of grace, we do not exclude the divine activity preserving grace in being, without which no one is capable of persisting either in the being of nature or the being of grace.