" a Christian man is in the Sabbath of his own heart, that is, in the quiet, tranquillity, and serenity of his conscience, undisturbed; "

― Augustine of Hippo , The Complete Works of Saint Augustine: The Confessions, On Grace and Free Will, The City of God, On Christian Doctrine, Expositions on the Book Of Psalms, ... (50 Books With Active Table of Contents)