A Patristic View of Signs and Wonders Pt. 2
This passage also answers the question, "Why am I not physically healed when I pray for it?"
It is easy now, when we see everything heading for destruction, to disengage our minds from love of the world. But then it was very difficult, because they [the apostles] were sent to preach the unseen kingdom of Heaven at the very time when everyone far and wide could see the kingdoms of earth flourishing. And so miracles were granted to the holy preachers, that their evident power might lend credence to their words, and that those who preached something new might perform something new. It is said in the same reading [St. Matthew 10], "Cure the sick, raise the dead, cleanse lepers, cast our demons."Read Post One, quoting St. Isaac the Syrian.
With the world flourishing, the human race increasing, the body enduring long in this life, riches abounding, who would believe that there was another life when he heard of it, who would prefer invisible to visible things? But with the sick returning to health, the dead rising to life, lepers being cleansed, demoniacs being snatched from the power of unclean spirits -- when so many visible miracles had been performed, who would not believe what he heard about invisible things? In truth visible miracles shine forth to attract the hearts of those who see them to faith in invisible things, so that from the wonder done externally what is interior and far more wonderful may be realized.
So now too, when the number of believers has grown, there are many within the holy Church who pursue the life of the virtues, but they lack the signs of the virtues, because it is useless for a miracle to be shown externally if there is nothing to be done interiorly. It was for this reason that Paul said that "signs are for unbelievers, not believers"; for this reason that this outstanding preacher raised up Eutychus by his prayer in the presence of all unbelievers, when he slept during his preaching and fell from the window and died; but he did not cure Timothy, his companion on his travels from the weakness of his stomach by a word, but restored him by his healing art, saying: "Use a little wine for the sake of your stomach and your frequent illnesses." If he revived by prayer a weak unbeliever who was, as we believe, dead, why did he not save his sick companion by a prayer? It is undoubtedly because the former who was still inwardly not alive had to be healed outwardly by a miracle so that an inner power might bring him to life through what the exterior one made manifest, whereas the signs were not to be displayed outwardly in the case of the sick believer, who was completely alive inwardly.
— Pope St. Gregory the Great. Homily 17 from Forty Gospel Homilies. (Kalamazoo, MI: Cistercian Publications, 1990), pp. 122-3.