Thelema is a philosophy of life base on the rule or law, "Do what thou wilt." The ideal of "Do what thou wilt" and its association with the word Thelema goes back to François Rabelais, but was more fully developed and proselytized by Aleister Crowley, who founded a religion named Thelema based on this ideal. The word itself is the English transliteration of the Koine Greek noun θέλημα: "will", from the verb θέλω: to will, wish, purpose. Early Christian writings use the word to refer to the will of God, the human will, and even the will of God's opponent, the Devil.