Gnosis is the common Greek noun for knowledge (in the nominative case γνῶσις f.). It generally signifies a dualistic knowledge in the sense of mystical enlightenment or "insight". Gnosis taught the 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. The term is used in the context of ancient religions and philosophies, aspects of Judeo-Christian beliefs, particularly to the ideas that emerged during early Christian and Greco-Roman interaction during the 2nd century.