Optimism is a wish without warrant; Christian hope is a certainty, guaranteed by God himself. Optimism reflects ignorance as to whether good things will ever actually come. Christian hope expresses knowledge that every day of his life, and every moment beyond it, the believer can say with truth, on the basis of God's own commitment, that the best is yet to come.
J. I. PackerThe weaker we feel, the harder we lean. And the harder we lean, the stronger we grow spiritually, even while our bodies waste away.
J. I. Packer