"Inasmuch," says he, "as not to sin is ours, we are able to sin and to avoid sin." What, then, if another should say: "Inasmuch as not to wish for unhappiness is ours, we are able both to wish for it and not to wish for it?" And yet we are positively unable to wish for it. For who could possibly wish to be unhappy, even though he wishes for something else from which unhappiness will ensue to him against his will? Then again, inasmuch as, in an infinitely greater degree, it is God's not to sin, shall we therefore venture to say that He is able both to sin and to avoid sin? God forbid that we should ever say that He is able to sin! For He cannot, as foolish persons suppose, therefore fail to be almighty, because He is unable to die, or because He cannot deny Himself. What, therefore, does he mean? by what method of speech does he try to persuade us on a point which he is himself loth to consider? For he advances a step further, and says: "Inasmuch as, however, it is not of us to be able to avoid sin; even if we were to wish not to be able to avoid sin, it is not in our power to be unable to avoid sin." It is an involved sentence, and therefore a very obscure one. It might, however, be more plainly expressed in some such way as this: "Inasmuch as to be able to avoid sin is not of us, then, whether we wish it or do not wish it, we are able to avoid sin!" He does not say, "Whether we wish it or do not wish it, we do not sin," -- for we undoubtedly do sin, if we wish; -- but yet he asserts that, whether we will or not, we have the capacity of not sinning, -- a capacity which he declares to be inherent in our nature. Of a man, indeed, who has his legs strong and sound, it may be said admissibly enough, "whether he will or not he has the capacity of walking;" but if his legs be broken, however much he may wish, he has not the capacity. The nature of which our author speaks is corrupted. "Why is dust and ashes proud?" 
It is corrupted. It implores the Physician's help. "Save me, O Lord," 
is its cry; "Heal my soul," 
it exclaims. Why does he check such cries so as to hinder future health, by insisting, as it were, on its present capacity?