Spiritual Exercises by Gertrud the Great of Helfta
The most scholarly of the remarkable nuns of Helfta composed these meditations, rituals, prayers, instructions on how to pray, chants, hymns, and litanies in the late thirteenth century. Her mastery of poetic prose attests to the level of women's education in the highly cultured abbey she entered as a child of five and never, so far as we know, left even once.