From St. John of Kronstadt’s “My life in Christ”
You ask the Lord that you may love Him with a love, strong as death, or until death. Suppose, now, that the Lord sends you a terrible inward disease that may bring you nigh unto death itself. Do not, then, murmur against the Lord, but bear it bravely, thanking the Lord for His fatherly visitation, and this will show that what you call your love for God is strong as death. And during the most violent fits or spasms of your illness trust in God, that He has the power to save you, not only from suffering, but even from death itself, should it please Him to do so. Do not spare, do not cherish your perishable body, but give it up willingly and wholly to the Lord, as Abraham gave his son Isaac as an holocaust, to the will of the Lord Who punishes you—not losing faith in God’s goodness, not growing despondent, not foolishly accusing God of injustice for so severely chastising you—and you will thus offer a great sacrifice unto God, like Abraham or like the martyrs.