"Abba Seridos was gravely ill one day, afflicted with a high fever that would not subside. Nevertheless, he did not ask God to heal him or even lessen his suffering. He asked only that God would grant him endurance and a spirit of thanksgiving."
This, of course, does not exclude the petitions for healing. However, the Fathers clearly teach that, while illness is a product of the Fall and is contrary to our nature, physical suffering is used by God to bring about repentance and the healing of our souls. For us to profit from our sickness we must see it through God's eyes. As St. Gregory of Nazianzuz writes,
"I don't wish ... that you should agonize over your suffering as if it were incurable or irredeemable. Rather I should want you to be philosophical about your suffering and show yourself superior to the cause of your affliction, beholding in the illness a superior way towards what is ultimately good for you."
The "superior way" for us is the path of the virtues. In times of illness, a Eucharistic attitude (1 Thess. 5:18) is both a means toward God and the telos of our life. Abba Poemen says,
"If three men meet, and one preserves interior peace, the second gives thanks to God in illness, and the third serves with purity of thought, these three accomplish the same work."