In [Chapter 27, King Wonderful-Adornment as the Previous Life of a Bodhisattva], the Buddha recounts that, once awakened to the dharma, King Śubhavyūha said that his two sons were his “good friends,” because they had enabled him to meet the Buddha. The Buddha underscores the point, saying: “You should know that a good friend is indeed the great spur [literally, “the great cause and condition”] that brings inspiration to others, causing … the thought of highest, complete enlightenment to awaken in them.” This passage has often been quoted to stress the importance of a “good friend” on the Buddhist path. This expression (Skt. kalyāvamitra; J. zenchishiki), also translated as “teacher” or “spiritual advisor,” broadly refers to one who assists another on the Buddhist path. Zhiyi, for example, divides “good friends” into the three categories of patrons, fellow practitioners, and teachers. The term has been variously interpreted. For example, in premodern Japan, in addition to its broader meaning of one who assists another’s practice, a “good friend” meant the ritual attendant who assisted someone at the time of death, helping that person to focus his or her thoughts on a buddha — usually Amitābha — in order to achieve birth in his pure land.

Nichiren gave considerable thought to the concept of a “good friend” and interpreted it in light of his understanding of the Final Dharma age. In an early but important essay called “On Protecting the Country,” he poses the question: In this deluded age, the Buddha has departed, and great teachers such as Nāgārjuna or Zhiyi no longer make an appearance. How then can one escape samsaric suffering? Because there are no worthy human teachers, Nichiren concluded that, in this age, the Lotus and Nirvāṇa sūtras are to be accounted “good friends,” in accord with Zhiyi’s statement: “At times following a good friend, and at times following the sūtra scrolls, one hears … the single truth of enlightened wisdom.” Nichiren’s insistence that the Lotus Sūtra is the “good friend” for the present age is perfectly in line with his frequent admonition, drawn from the Nirvāṇa Sūtra, to “rely on the dharma and not on the person.”

What one should most avoid, Nichiren asserted, were “evil friends,” teachers such as Kūkai, who had said that the Lotus Sūtra was inferior to the esoteric teachings, or Hōnen, who had insisted that the Lotus should be set aside as beyond human capacity to practice in the latter age. When Nichiren spoke of such people as “evil friends,” he meant, not that they were morally corrupt or insincere, but that they were promoting incomplete teachings that, in his understanding, no longer led to buddhahood in the Final Dharma age. Occasionally he cited a passage from the Nirvāṇa Sūtra, which says that “evil friends” are more to feared than mad elephants. It states, “Even if you are killed by a mad elephant, you will not fall into the three evil paths. But if you are killed by an evil friend, you are certain to fall into them. A mad elephant is merely an enemy of one’s person, but an evil friend is an enemy of the good dharma. Therefore, bodhisattvas, you should at all times distance yourselves from evil friends.” For his part, Nichiren expressed the fervent hope that people would “not mistakenly trust in evil friends, adopt false teachings, and spend their present life in vain.” This was the impetus behind his assertive proselytizing.

[I]n asking their parents’ permission — a requirement of the monastic rule — to renounce household life and become Buddhist monks, the two princes state that it is “difficult to meet a buddha, just as it is to see udumbara flowers or for a one-eyed turtle to find the hole in a floating piece of wood.” The uḍumbara tree was said to bloom once every three thousand years and thus stands as a symbol for an extremely rare opportunity. The same analogy occurs in the “Skillful Means” chapter to illustrate the rarity of hearing the Lotus Sūtra.

The analogy of the turtle and the floating piece of wood appears in a number of sūtras and commentaries, where it is used to illustrate the rarity of being born human and encountering the Buddha’s teaching. In a letter to a follower, the wife of the same Matsuno Rokurōzaemon mentioned above, Nichiren develops the analogy in great detail and applies it specifically to the Lotus Sūtra. To summarize his expanded version: A large turtle with only one eye and lacking limbs or flippers dwells on the ocean floor. His belly is burning hot, but the shell on his back is freezing cold. Only the rare red sandalwood has the power to cool the turtle’s belly. The turtle yearns to cool his belly on a piece of floating red sandalwood and at the same time to warm his back in the sun. However, he can rise to the ocean’s surface only once in a thousand years, and even then, he can rarely find a piece of floating red sandalwood. When he does so, it may not contain a hollow, or at least not one of the proper size to hold him. Even when he finds a floating sandalwood log with an appropriate hollow place, without limbs, he cannot easily approach it, and having only one eye, he mistakes east for west; thus, he cannot accurately judge the direction of the log’s drift and winds up moving in the wrong direction. Nichiren interprets: “The ocean represents the sea of the sufferings of birth and death, and the turtle is ourselves, living beings. His limbless state indicates our lack of good roots. The heat of his belly represents the eight hot hells of anger, and the cold of the shell on his back, the eight cold hells of greed. His remaining for a thousand years on the ocean floor means that we fall into the three evil paths and are unable to emerge. His surfacing only once every thousand years illustrates how difficult it is to emerge from the three evil paths and be born as a human even once in immeasurable eons, at a time when Śākyamuni Buddha has appeared in the world.”

The turtle mistaking east for west, Nichiren continues, means that ordinary people in their ignorance confuse inferior and superior among the Buddha’s teachings, clinging to provisional teachings that have lost their efficacy and rejecting the one teaching that can lead to enlightenment. And the rarity of the turtle finding a floating sandalwood log with a hollow in it just big enough to hold him means that “even if one should meet the Lotus Sūtra, it is rarer and more difficult still to encounter the daimoku, which is its heart, and chant Namu Myōhō-renge-kyō.” In this way, Nichiren stressed the inconceivable good fortune of his followers, who had not only been born as humans and met the Lotus Sūtra but, although living in a degenerate age in a remote country far from the Buddha’s birthplace, were able to chant the wonderful dharma of the daimoku.