Meister Eckhart (1328) was the central figure within the so called Rhenish mysticism. When he served as the prior of the Dominican monastery at Erfurt in the late thirteenth century, he wrote the treatise presented here in modern German. Here, we find him more as a spiritual counselor than as a speculative philosopher who answers to questions and problems raised by his brothers. Against a background of mystical interior piety, he traces the issues of monastic as well as average Christian behavior. He speaks about human sinfulness as well as about imitation of Christ and the communion in the Lord's Supper. The commentaries reveal the historical context of the treatise as well as its impact on our days as a handbook of Christian life.