Yes. Good is the cause of evil because evil in no way has any but an accidental cause.
Evil is the absence of the good which is natural and due to a thing. But that anything fail from its natural and due disposition can come only from some cause drawing it out of its proper disposition.
But only good can be a cause; because nothing can be a cause except inasmuch as it is a being, and every being, as such, is good.
If we consider the four special kinds of causes, we see that the agent, the form, and the end, import some kind of perfection which belongs to the notion of good. Even matter, as a potentiality to good, has the nature of good.
Now that good is the cause of evil by way of the material cause was shown above (Q48, A3). For it was shown that good is the subject of evil.
But evil has no formal cause, rather is it a privation of form.
Likewise, neither has it a final cause, but rather is it a privation of order to the proper end; since not only the end has the nature of good, but also the useful, which is ordered to the end.
Evil, however, has a cause by way of an agent, not directly, but incidentally.
Evil has a deficient cause in voluntary things otherwise than in natural things. For the natural agent produces the same kind of effect as it is itself, unless it is impeded by some exterior thing; and this amounts to some defect belonging to it. Hence evil never follows in the effect, unless some other evil pre-exists in the agent or in the matter.
But in voluntary things the defect of the action comes from the will actually deficient, inasmuch as it does not actually subject itself to its proper rule. This defect, however, is not a fault, but fault follows upon it from the fact that the will acts with this defect.
Evil has no direct cause, but only an incidental cause.