Character cannot be developed in ease and quiet. Only through experience of trial and suffering can the soul be strengthened, ambition inspired, and success achieved.
-Helen Keller

From "A Troubled Guest: Life and Death Stories" by Nancy Mairs:

Beneath my interest in death, as in disability before it, lay my desire to understand the role of affliction in perfecting human experience. Although suffering is a state often considered scandalous in modern society, a mark of illness to be cured or moral deviance to be corrected, from a spiritual perspective it is simply an element in the human condition, to be neither courted nor combated. To refuse to suffer is to refuse fully to live. Doing so leads not only to risky behaviors (self-mutilation, anorexia nervosa, and addiction all stem from an inauthentic relation to suffering) but also to an anesthesia of the soul which renders play all but impossible. In short, suffering needs to be redeemed and reincorporated into the framework we use to ascribe meaning to otherwise chaotic experience. Without death to round our little lives, they have neither shape nor sweetness nor significance.