Gnosis is the common Greek noun for knowledge (in the nominative case γνῶσις f.). In Christian, Islamic, or Jewish mysticism, mystery religions and Gnosticism gnosis generally signifies a spiritual knowledge or "religion of knowledge", in the sense of mystical enlightenment or "insight". Gnosis taught a deliverance of man from the constraints of earthly existence through insight into an essential relationship, as soul or spirit, with a supramundane place of freedom.