What we should chant all the time as the practice of the perfect teaching is “Namu Myōhō Renge Kyō,” and what we should keep in mind is the way of meditation based on the truth of “3,000 existences contained in one thought.” Only wise men practice both chanting “Namu Myōhō Renge Kyō” and meditating on the truth of “3,000 existences contained in one thought.”
Jisshō-shō, A Treatise on the Ten Chapters of the Great Concentration and Insight