The Ladder of Divine Ascent, written by John, abbot of Sinai, describes the ascent of the monk in thirty rungs, corresponding to the hidden years of Christ, from renunciation through the struggle with the passions to stillness, prayer, dispassion and love. It is read in Orthodox monasteries during Lent.
Ladder of Divine Ascent
John Climacus’s seventh-century guide to monastic life in thirty steps.
Also: Scala Paradisi, Climacus