What a fool, quoth he, am I, thus to lie in a stinking dungeon, when I may as well walk at liberty! I have a key in my bosom, called Promise, that will, I am persuaded, open any lock in Doubting Castle.
John Bunyan, Thomas Scott (1825). “The Pilgrim's Progress: From this World to that which is to Come. Delivered Under the Similitude of a Dream. In Two Parts”, p.161
