To all hastening to write their names in the book of life in the heavens, the present book is a surpassing path. Traveling by this path, we shall see that it infallibly guides those who follow its instructions, preserves them invulnerable to every obstacle and presents to us a firmly-based ladder leading us up from the earthly to the holy of holies, at the summit of which is the God of love.

John Climacus, The Ladder of Divine Ascent (6th century, CE)