We have explained the first remedy against each of the temptations of the devil; now we shall explain the second remedy, which will be common to all temptations. This great and salutary remedy consists in prayer — whether the sick man can pray for himself, or others pray for him, or the prayer of the sick man and of those standing by is joined together. For it is certain that the prayer of those who fear God avails much, especially since we hold it for certain that the devil cannot tempt except as far as the Lord permits him. For he is like a roaring lion, or a mad dog bound with an iron chain, who cannot bite at his own pleasure, but only as much as God — who holds the chain in His most powerful hand — allows him to bite. This is taught above all by St. Augustine, expounding those words of the Psalm: "Say to my soul: I am your salvation." (Ps. 34:3.) And adducing the example of Job: "God showed this," he says, "in the case of that holy man Job: that the Devil himself has no power to take away these temporal goods unless he has received it from that sovereign Power. He could envy the holy man — but could he harm him? He could accuse — but could he have dominion over him? Did he even wish to hurt him without saying to God: 'Put forth Your hand'? What is 'Put forth Your hand'? Give power. He received it; Job was tempted — yet, tempted, he conquered; the tempter was conquered. For God, who had permitted the Devil to take those things away, had not abandoned His servant inwardly; and the Devil himself had to be overcome by the soul of His servant — of man, I say. Conquered in paradise, he conquered on the dunghill. There he was conquered by the Devil through the woman; here he conquered both the Devil and the woman." This very thing that St. Augustine teaches — that the devil can do nothing except as much as God permits — St. Anthony and St. Francis of Assisi taught by their example. Of St. Anthony, St. Athanasius, who wrote his life, speaks thus: "Antony, when a multitude of demons gathered against him as if for battle, used to say, playing as it were with his enemies: 'Since you are broken, the Lord enfeebling you, you try by your numbers to strike terror — though this very thing is a sign of weakness, that you put on the shapes of irrational beasts.' And again he said with confidence: 'If you have any power, and the Lord has given you power over me, devour what has been given over to you; but if you cannot, why do you strive in vain? For the sign of the Cross and faith in the Lord is for us an impregnable wall.'"
Of St. Francis, St. Bonaventure relates nearly the same: "Seeking solitary places," he says, "he would go at night to abandoned solitudes to pray, where he frequently endured horrible battles with demons, who strove to disturb him in his devoted attention to prayer. (St. Bonaventure, Life of St. Francis, ch. 10.) But he, armed with heavenly weapons, the more violently he was attacked by the enemies, the stronger he became in the work; confidently saying to Christ: 'Under the shadow of Your wings protect me from the face of the wicked who have afflicted me.' And to the demons: 'Do whatever you can against me, you malignant and deceitful spirits. For you can do only as much as the hand from above permits you; and I stand ready with all joy to endure whatever He shall decree to inflict.' Unable to endure such constancy of mind, the proud demons departed in confusion." With this most solid foundation therefore laid — that the devil can do nothing except as much as God permits him — it cannot be doubted that fervent prayer to God, whether of the sick man or of others on his behalf, avails much, especially if those who pray are friends of God. We have a most illustrious example of this in St. Gregory, in the fourth book of the Dialogues, who also says that this very example occurred in his own monastery and that he related it while preaching. These are his words: "He of whom I remember having already spoken in homilies before the people," he says, "was a very restless boy named Theodore, who followed his brother into my monastery more from necessity than from choice. (Dial., bk. 4, ch. 3.) It was indeed burdensome to him if anyone said anything for his salvation, for he could not only not do good, he could not even bear to hear of it. By swearing, by anger, by mockery, he kept declaring that he would never come to the habit of holy living. Now in that plague which lately consumed a great part of the people of this city, he was struck in the groin and brought to the point of death. And as he breathed his last, the Brethren gathered to protect his passing by their prayers. His body had already died from the extremities inward; only in his breast did the vital warmth still gasp. All the Brethren therefore began to pray the more earnestly for him, as they saw him departing so quickly. Then he suddenly began to cry out to the same Brethren standing by, and with loud cries to interrupt their prayer, saying: 'Withdraw! Behold, I have been given to a dragon to be devoured, and because of your presence he cannot devour me; he has already swallowed my head in his mouth. Give place, that he may torment me no longer but do what he is about to do. If I have been given to him to devour, why should I suffer delay on your account?' Then the Brethren began to say to him: 'What are you saying, brother? Imprint the sign of the holy Cross upon yourself.' He answered: 'I want to sign myself, but I cannot, for I am being crushed by the scales of this dragon.' When the Brethren heard this, prostrate on the ground with tears they began to pray still more vehemently for his deliverance. And behold, suddenly the sick man began to cry out: 'Thanks be to God! Behold, that dragon which had received me to devour has fled; driven out by your prayers, he could not stand. Now intercede for my sins, for I am ready to be converted and to abandon secular life entirely.' The man, therefore, who — as has been said — had already died from the extremities of his body, was preserved for life and converted to God with his whole heart; and after, changed in heart, he had for a long time kept himself under the discipline of the scourge, his soul was at last loosed from the flesh." So far St. Gregory.
Let those therefore who assist the dying learn not so much to talk with the sick man as to pray ardently to God for him; and not to admit just anyone to visit a sick man placed in his last moments, but devout and upright men whose prayers may avail much with God. For the constant and fervent prayer of a just man avails much. And just as the Devil, because he has but a short time, leaves no stone unturned at that critical moment, so too — and much more — ought faithful friends to help with prayers and tears their brethren who are departing from this present world.