Why are we naturally drawn to joyful people? One reason, I believe, is that joy is a sign of God’s presence, which is naturally attractive to us. God’s joy speaks to the joy that dwells sometimes hidden in our hearts. “Deep calls to deep,” as Psalm 42 says. Or, as St. Augustine wrote, “Our hearts are restless until they rest in you, O Lord.” Augustine, a fourth-century North African theologian, understood something fundamental about human beings: we naturally desire God, the source of all joy. We are drawn to joy because we are drawn to God.
— James Martin, Between Heaven and Mirth, p. 29