“Love one another and you will be happy. It’s as simple and difficult as that.”

Source: The Sisterhood of the Traveling Pants

Source: What Dreams May Come

Source: Midnight all Day

On est heureux par soi-même quand on sait s'y prendre, avoir des goûts simples, un certain courage, une certaine abnégation, l'amour du travail et avant tout une bonne conscience.
Letter to Charles Poney, (16 November 1866), published in Georges Lubin (ed.) Correspondance (Paris: Garnier Freres, 1964-95) vol. 20, p. 188; André Maurois (trans. Gerard Hopkins) Lélia: The Life of George Sand (New York: Harper, 1954) p. 418
Variant: One is happy once one knows the necessary ingredients of happiness: simple tastes, a certain degree of courage, self denial to a point, love of work, and above all, a clear conscience.
Source: Correspondance, 1812-1876, Volume 5

Jesus in John 13:34-35 NRSV
Gospel of John

Source: Dear John

The Elements of True Piety (c. 1677), The Shorter Leibniz Texts (2006) http://books.google.com/books?id=oFoCY3xJ8nkC&dq edited by Lloyd H. Strickland, p. 189

Source: Hiss of Death

From Are You the One for Me? (1992)