An idol of शिव in काशी . This idol is called ॐकार also. भगवान् परमेश्वर who gives मोक्ष to men dwells in this idol in the form of पञ्चायतन . The five souls of शिव are the five आयतन s. They are शान्ति (tranquillity), अतीतशान्ति (passed beyond tranquillity), परापरविद्या (Greater and smaller knowledge), प्रतिष्ठा (celebrity) and निवृत्ति (Recession). Because these five आयतन s dwell in the idol of शिव at काशी it got the name पञ्चायतन . (Chapter 34, Padma Purāṇa)