Hermes Trismegistus is the purported author of the Hermetic Corpus, a series of sacred texts that are the basis of Hermeticism. He may be a representation of the union of the Greek god Hermes and the Egyptian god Thoth, both gods of writing and of magic. As a divine source of wisdom, Hermes Trismegistus was credited with tens of thousands of writings of high standing. Many Christian writers considered Hermes Trismegistus to be a wise pagan prophet who foresaw the coming of Christianity. The addition of "thrice-great" was added to his name because he knew the three parts of the wisdom of the universe; alchemy, astrology, and theurgy. The Asclepius and the Corpus Hermeticum are the most important of the Hermetica, writings attributed to Hermes Trismegistus, which survive. Hermeticism was a magical and religious movement that were considered greatly important during both the Renaissance and the Reformation.