In Chih-i’s system, various types of the Buddha’s teaching are arranged in an ascending order, so that beings can be led to receive the final teaching of the Buddha. To Chih-i, the final teaching of the Buddha should express the most profound doctrine, and the Origin in which the eternal Buddha abides can be regarded precisely as such a doctrine, whereby the Lotus Sūtra is legitimized to be the final teaching of the Buddha. (Vol. 2, Page 402)