Sefer Yetzirah (the "Book of Creation") is the title of the earliest extant book of Jewish esotericism. This short, enigmatic book describes how God created the universe through “32 secret paths of wisdom,” composed of the 22 letters of the Hebrew alphabet plus the ten “sefirot,” which in this early period refer simply to “numbers” even as they allude to metaphysical principles. The origin of the text is unknown and debated. Based on the language of the text, scholars date it to between the third and sixth centuries, admitting some later additions. Some attribute its origin to Abraham the patriarch and others to the tanna R. Akiva, who, according to the Babylonian Talmud, engaged in mystical activities. Given the subject matter and the work’s laconic style, it has been the subject of many varied commentaries.