Joy is the effect of love with which one endures pain.

Serve the Lord without sighing. With a joyful face and courage, demonstrate how true the Lord's words are: "My yoke is easy and my burden is light"... Keep a smile on your face and view suffering in a nobler light, in which suffering appears as an expression of God's love for you and a reason for joy. Joy is not a virtue, but the effect of the love with which pain is borne.

(Titus Brandsma /1881–1942/, retreats for religious sisters)