Whether God Is a Cause of Sin?
Objection 1: It would seem that God is a cause of sin. For the Apostle says of certain ones (Rom. 1:28): "God delivered them up to a reprobate sense, to do those things which are not right [Douay: 'convenient']," and a gloss comments on this by saying that "God works in men's hearts, by inclining their wills to whatever He wills, whether to good or to evil." Now sin consists in doing what is not right, and in having a will inclined to evil. Therefore God is to man a cause of sin.
Obj. 2: Further, it is written (Wis. 14:11): "The creatures of God are turned to an abomination; and a temptation to the souls of men." But a temptation usually denotes a provocation to sin. Since therefore creatures were made by God alone, as was established in the First Part (Q. 44, A. 1), it seems that God is a cause of sin, by provoking man to sin.
Obj. 3: Further, the cause of the cause is the cause of the effect. Now God is the cause of the free-will, which itself is the cause of sin. Therefore God is the cause of sin.
Obj. 4: Further, every evil is opposed to good. But it is not contrary to God's goodness that He should cause the evil of punishment; since of this evil it is written (Isa. 45:7) that God creates evil, and (Amos 3:6): "Shall there be evil in the city which God [Vulg.: 'the Lord'] hath not done?" Therefore it is not incompatible with God's goodness that He should cause the evil of fault.
On the contrary, It is written (Wis. 11:25): "Thou . . . hatest none of the things which Thou hast made." Now God hates sin, according to Wis. 14:9: "To God the wicked and his wickedness are hateful." Therefore God is not a cause of sin.
I answer that, Man is, in two ways, a cause either of his own or of another's sin. First, directly, namely by inclining his or another's will to sin; secondly, indirectly, namely by not preventing someone from sinning. Hence (Ezech. 3:18) it is said to the watchman: "If thou say not to the wicked: 'Thou shalt surely die' [*Vulg.: "If, when I say to the wicked, 'Thou shalt surely die,' thou declare it not to him."] . . . I will require his blood at thy hand." Now God cannot be directly the cause of sin, either in Himself or in another, since every sin is a departure from the order which is to God as the end: whereas God inclines and turns all things to Himself as to their last end, as Dionysius states (Div. Nom. i): so that it is impossible that He should be either to Himself or to another the cause of departing from the order which is to Himself. Therefore He cannot be directly the cause of sin. In like manner neither can He cause sin indirectly. For it happens that God does not give some the assistance, whereby they may avoid sin, which assistance were He to give, they would not sin. But He does all this according to the order of His wisdom and justice, since He Himself is Wisdom and Justice: so that if someone sin it is not imputable to Him as though He were the cause of that sin; even as a pilot is not said to cause the wrecking of the ship, through not steering the ship, unless he cease to steer while able and bound to steer. It is therefore evident that God is nowise a cause of sin.