We have indeed a mark to guide us safely over the ocean of temptations; and why make the too curious inquiry, whether some with such thoughts as these have not fallen nevertheless, and why therefore despair, as if the achievement was beyond your reach? Look on him who has succeeded, and boldly launch upon the voyage with confidence that it will be prosperous, and sail on under the breeze of the Holy Spirit with Christ your pilot and with the oarage of good cheer. For those who go down to the sea in ships and occupy their business in great waters do not let the shipwreck that has befallen someone else prevent their being of good cheer; they rather shield their hearts in this very confidence, and so sweep on to accomplish their successful feat.

—Saint Gregory of Nyssa, On Virginity