Before Nichiren Shonin, Ichinen Sanzen was a theory that Buddhist practitioners attempted to understand through meditation. Nichiren Shonin, however, taught that Ichinen Sanzen could be realized through faith in the Odaimoku. At the very end of the Kanjin Honzon-sho, he wrote:

For those who are incapable of understanding the truth of the “3,000 worlds contained in one thought,” Lord Shakyamuni Buddha, with his great compassion, wraps this jewel with the five characters of Myo, Ho, Ren, Ge, and Kyo and hangs it around the necks of the ignorant in the decadent Latter age of the dharma.