According to Gudrun Bühnemann, the esoteric Hindu tantric traditions through texts such as "Tantra-tattva" follow elaborate Prana Pratistha rituals to infuse life into a "murti". Some tantra texts such as the "Pancaratraraksa" state that anyone who considers an icon of Vishnu as nothing but "an ordinary object" made of iron "goes to hell". The use of Murti and particularly the "prana pratistha" consecration ceremony, states Buhnemann, has been criticized by Hindu groups. These groups state that this practice came from more recent "false tantra books", and there is not a single word in the Vedas about such a ceremony.