The Nirvana Sūtra states also that benefits of understanding the teachings of the Buddha through such means as the “five periods,” “eight teachings (four doctrinal teachings and four methods of teaching),” provisional and true teachings, and Mahāyāna and Hinayāna doctrines are like the shadow of the tree, which is the doctrine of “The Life Span of the Buddha” chapter in the essential section of the Lotus Sūtra. The sūtra also declares that those who negate the eternal life of the Buddha are like a tree without a shadow in darkness. It means that benefits of those sūtras expounded by Śākyamuni Buddha during His lifetime before “The Life Span of the Buddha” chapter are likened to the shadow of a tree in darkness. They are of those who had listened to the teaching of “The Life Span of the Buddha” chapter and been planted with the seed of Buddhahood in the distant past. Those who had not received the seed have neither a tree nor a shadow to speak about.

Toki Nyūdō-dono Go-henji: Hongon Shukkai-shō, A response to Lay riest Lord Toki: Treatise on Overcoming Illusions of the Triple World by Provisional Teachins, Writings of Nichiren Shōnin, Doctrine 2, Page 277