"Naraka" in Vedas, is a place where souls are sent for the expiation of their sins. It is mentioned especially in dharmaśāstras, itihāsas and s but also in Vedic samhitas, Aranyakas and . Some Upanisads speak of 'darkness' instead of hell. A summary of , Bhagavad Gita, mentions hell several times. Even Adi Sankara mentions it in his commentary on Vedanta sutra. Except the views of Hindu philosopher Madhva, it is not seen as place of eternal damnation within Hinduism. Still, some people like members of Arya Samaj don't accept the existence of Naraka or consider it metaphorical.