John Cassian, Conferences I–X VI.4: How evil cannot be forced on any one by another against his will

Preserving then these distinctions clear and fixed, and knowing that there is nothing good except virtue alone, and nothing bad except sin alone and separation from God, let us now carefully consider whether God ever allows evil to be forced on his saints either by Himself or by some one else. And you will certainly find that this never happens. For another can never possibly force the evil of sin upon anyone, who does not consent and who resists, but only on one who admits it into himself through sloth and the corrupt desire of his heart. Finally, when the devil having exhausted all his wicked devices had tried to force upon the blessed Job this evil of sin, and had not only stripped him of all his worldly goods, but also after that terrible and utterly unlooked for calamity of bereavement through the death of his seven children, had heaped upon him dreadful wounds and intolerable tortures from the crown of his head to the sole of his foot, he tried in vain to fasten on him the stain of sin, because he remained steadfast through it all, never brought himself to consent to blasphemy.