Pantheism is the heresy that existence is equivalent to God. There is a related heresy of panentheism which suggests both that God is in everything and that everything is in God. Pantheistic and Panentheistic, or "natural" religions believe that god and everything in nature are aspects of a continuous spiritual plane, and are thus essentially inseparable. Pantheistic religions equate all of existence with the divine (the creator and the created are one), whereas panentheistic religions hold that the created universe is within the creator. Panentheism implies that, while the Creator is not reducible to or identical with the creation, creation is nonetheless an essential aspect of God's true essence (i.e., without the existence of the universe, God could not be, properly speaking, the Creator of anything). Examples include (to various degrees): the pantheistic and panentheistic schools of Shaivism and Vaishnavism in Hinduism, Ayyavazhi, Shintoism, and some animistic traditions. There have also been many examples of panentheistic theology in the Christian tradition, beginning in the medieval period and continuing into the 21st century.
See: In whom we live and move and have our being: panentheistic reflections on God's presence in a scientific world, 2004, ed. by Philip Clayton, Arthur Robert Peacocke