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.
Thelema as a philosophy of life, is based on the rule or law, “Do what thou wilt”.
It first appears in the work of Saint Augustine of Hippo (354-430) in the form “dilige, et quod vis fac” or “Love, and do what thou wilt”, by which Augustine meant that if you love God you are free to act according to your will, since a man who loves God will naturally select the path of virtue.
In the 16th century François Rabelais used Thélème, the French form of the word, as the name of a fictional Abbey in his famous books, Gargantua and Pantagruel. The only rule of this Abbey was “fay çe que vouldras” (“Fais ce que tu voudras”, or, “Do what thou wilt”). It is also seen quoted as “Ama Deum et fac quod vis” (“Love God, and do what you want”).
This rule was revived and used in the real world in the mid 18th century by Sir Francis Dashwood, who inscribed it on a doorway of his abbey at Medmenham, where it served as the motto of The Hellfire Club.
King Pausole, a character in Pierre Louÿs’, Les aventures du roi Pausole (The Adventures of King Pausole, published in 1901), had a similar motto of “Do what you like as long as you harm no one”.
In 1904 by Aleister Crowley used both the phrase “Do what thou wilt” and the word Thelema in Greek in The Book of the Law. Crowley took the word Thelema for the name of the philosophical, mystical and religious system which he subsequently developed. This system includes ideas from occultism, Yoga, and both Eastern and Western mysticism (especially the Qabalah).
Shri Gurudev Mahendranath, in speaking of svecchachara, the Sanskrit equivalent of the phrase “Do what thou wilt”, wrote that “Rabelais, Dashwood, and Crowley must share the honor of perpetuating what has been such a high ideal in most of Asia.”
The Wiccan Rede is used by followers of the Wiccan religion. The most common form of the Rede is “An it harm none, do what ye will”. The Rede in its best known form as the “eight words” couplet was first publicly recorded in a speech by Doreen Valiente in 1964.