Source, in full
"Sermon pour la fête de la Circoncision de Notre-Seigneur" ["Sermon on the Circumcision"] in Oeuvres complètes, vol. 5 (Paris: Outhenin-Chalandre, 1840) p. 264. Preached at Metz. Quoted by Napoleon on leaving England for St. Helena. Reported in Hoyt's New Cyclopedia of Practical Quotations (1922) p. 222