Trees grow stronger because of the wind.
Why, then, do you wonder that good men are shaken in order that they may grow strong?
No tree becomes rooted and sturdy unless many a wind assails it. For by its very tossing it tightens its grip and plants its roots more securely; the fragile trees are those that have grown in a sunny valley.
It is, therefore, to the advantage even of good men, to the end that they may be unafraid, to live constantly amidst alarms and to bear with patience the happenings which are ills to him only who ill supports them.
Seneca, Roman Philosopher (65 A.D.)