In order to support his classification about the number of positions of the Perfect Teaching, Chih-i quotes citations from the Lotus Sūtra to demonstrate that this is not his own creation. In actuality, the Fourfold Teaching is his own system of classifying the teaching of the Buddha, and his illustration of the position of the Perfect Teaching is certainly derived from his own understanding of Buddhism.

With regard to the Position of the Five Preliminary Grades of Disciples, Chih-i argues that the chapter on Fen-pieh Kung-te P’in (Distinguishing Merits and Virtues) in the Lotus Sūtra provides a description of these positions. In the chapter on Fang-pien P’in (Expedient Means), the phrase about “to cause sentient beings to open the Buddha’s knowledge and insight” (Yü-ling Chung-sheng K’ai-fo Chih-chien) denotes the Ten Dwellings; “to reveal the Buddha’s knowledge and insight” (Shih-fo Chih-chien) signifies the Ten Practices; “to be awakened to the Buddha’s knowledge and insight” (Wu-fo Chih-chien) indicates the Ten Merit transferences; “to enter the Buddha’s knowledge and insight” (Ju-fo Chih-chien) denotes the Ten Stages, and the Stage of Preliminary Enlightenment. The Stage of Subtle Enlightenment is revealed in the citation “only Buddhas and Buddhas can exhaust the Ultimate Truth of all dharmas” (Wei Fo-yü-fo Nai-neng Chiu-ching Chu-fa Shih-hsiang). These associations of various phrases in the Lotus Sūtra with various positions are made by Chih-i according to his teacher Hui-ssu’s explanation. Moreover, Chih-i stresses that the number of positions of the Perfect Teaching in severing and destroying ignorance is for an expedient purpose only. By nature, positions of the Perfect Teaching are inconceivable: integrated, they can become a single position; divided, they can be of various levels. (Vol. 2, Page 222-223)