A Jewish mystical belief system claimed to have been practiced since God spoke to the Patriarchs but which historically gained significant popularity sometime before the 10th century AD. It is based on the belief that God is actually not a transcendant being but was itself created and made Creation through the emanations of a higher, transcendant power called the Ain Soph or Eyn Soph (transliteration varies). These emanations took the form of the Tree of Life (Etz Chayim).