Teresa of Ávila Quote

Keep this in mind, for it is very important advice, so do not neglect it until you find you have such a fixed determination not to offend the Lord that you would rather lose a thousand lives and be persecuted by the whole world, than commit one mortal sin, and until you are most careful not to commit venial sins.

Book called Way of perfection. Interior castle. Conceptions of the love of God. Exclamations of the soul to God (ed. 1972)