Book excerpt: Regardless of their sometimes ambiguous concepts of God, the Roman Stoic philosophers did acknowledge Him, but on the basis of reason alone, because they had not met Christ. Nonetheless, they did deduce from God's existence our need to live lives of virtue, honor, tranquility, and self-control--and they developed effective techniques to help us achieve this. Musonius Rufus the teacher, Epictetus the slave, Seneca the adviser to emperors, and Marcus Aurelius, the emperor himself, produced a practical technology we can use to integrate Christian ethics into our own daily practice. As Kevin Vost so wonderfully illustrates in his new book, The Porch and the Cross, the Stoics can help us learn--and remember--what is up to us, and what is up to God alone.