John Piper, from Suffering and the Sovereignty of God, page 25:
It is right and good to pray for healing. God has purchased it in the death of his Son, with all the other blessings of grace, for all his children (Isa. 53:5). But he has not promised that we get the whole inheritance in this life. And he decides how much. We pray, and we trust his answer. If you ask your Father for bread, he will not give you a stone. If you ask him for a fish, he will not give you a serpent (see Matt. 7:9- 10). It may not be bread. And it may not be a fish. But it will be good for you. That is what he promises (Rom. 8:28)
The Works of God 
this is good. often times people, when they find out about my ever-increasing blindness, are horrified. they assure me emphatically of their prayers for my healing.
i reassure them that i appreciate their prayers, and am confident that God is answering them. in a sense, i hope it is in this life, but certainly in the next i will see what “eye has not seen”, things that have never even entered human imagination.
i can wait.