Thirumantiram is a Tamil poetic work, written either in the 6th century CE by Tirumular. It is the tenth of the twelve volumes of the Tirumurai, the key texts of Shaiva Siddhanta and the first known Tamil work to use the term. The Tirumantiram is the earliest known exposition of the Shaiva Agamas in Tamil. It consists of over three thousand verses dealing with various aspects of spirituality, ethics and praise of Shiva. But it is more spiritual than religious and one can see the difference between Vedanta and Siddhanta from Tirumular's interpretation of the Mahavakyas. According to historian Venkatraman, the work covers almost every feature of the siddhar of the Tamils. According to another historian, Madhavan, the work stresses on the fundamentals of Siddha medicine and its healing powers. It deals with a wide array of subjects including astronomy and physical culture.