Please read the sūtra carefully, so that you may understand that the doctrine of “mutual possession of ten realms” is clearly preached in it. For instance, we read in the second chapter that the purpose of the Buddha appearing in the world was “to cause all living beings to open their gates to the insight of the Buddha.”

Interpreting this passage in the Lotus Sūtra, T’ien-t’ai said: “If the insight of the Buddha does not exist in all living beings, how can He open the gate to it? You should know from this that the insight of the Buddha is inherent in the minds of all living beings.” And Chang-an declared: “If the insight of the Buddha is non-existent in living beings, how can anyone cause them to open the gate to or be aware of it? For instance, how can a poor woman without a treasure house show off
treasure?”

Kanjin Honzon-shō, A Treatise Revealing the Spiritual Contemplation and the Most Verable One, Writings of Nichiren Shōnin, Doctrine 2, Page 142