Maurice Maeterlinck said this quote

He is wise who at last sees in suffering only the light that it sheds on his soul; and whose eyes never rest on the shadow it casts upon those who have sent it towards him. And wiser still is the man to whom sorrow and joy not only bring increase of consciousness, but also the knowledge that something exists superior to consciousness even. To have reached this point is to reach the summit of inward life, whence at last we look down on the flames whose light has helped our ascent.