Gregory of Nyssa's treatise On Perfection is addressed to a monk named Olympios who asked direction for attaining perfection. The treatise, which is in the form of a letter, is based almost exclusively upon Paul's great Christological texts which Gregory sets forth as the best guide to imitate Christ. As the treatise unfolds, we see a picture of sanctification which is both a result of human effort and God's good grace. Fellowship (koinonia) in Christ's name, the "one name by which we are called Christians"(J.174), is perceived by Gregory as a gift to which we thankfully(2) respond by our "determination" (spoude). Saint Paul is set forth as the "especially sure guide"(3) that is, he is a model or "imitation (mimeis) of Christ by a life according to virtue" (J.196).