Rabbi Isaac Ben Solomon Luria was one of the most famous Jewish mystics and scholars of the Kabbalah. He lived during the 16th century, in Egypt and Jerusalem. He wrote several famous commentaries on the Zohar, the most important book of the Kabbalah, and a great deal of mystical poetry, before deciding that he could only instruct his students orally.
Luria believed that he could communicate, mystically, with the souls of dead tzaddikim (saints or persons of great righteousness), and claimed frequent communication with the prophet Elijah. Many of his works on the Kabbalah made their way back to Europe and influenced Christian religious thinkers during the Italian Rennaisance.