"... the Two Dharmas of the Causal Practices and Effect [Virtues] of Lord Shakya are fully possessed in the Five Characters 'Myo ho ren ge kyo'; when we receive and keep these Five Characters He spontaneously yields and assigns [to us] the merits of those Causes and Effect" (Kanjin Honzon sho, STN, v. 1, 711).
"One receives because of faith; one keeps because of recalling." (Hokke mongu (Text Commentary on the Lotus Sutra) T.34.107c).
"The people who hear and receive this Sutra are many; the people who, as they have truly heard and received it, though great persecutions come, keep it in memory and do not forget it are few. To receive it is easy; to keep it is difficult. Therefore, attaining Buddhahood lies in keeping. The persons who would keep this Sutra keep it with the understanding that they shall encounter persecution.There is no doubt that 'They then will quickly obtain The Supreme Buddha Way' ["Chapter of the Jeweled Stupa"11 (T.9.34b)]. To recall 'Namu Myoho renge kyo' which is the Great Matter of the Buddhas of the Three Eras [Past, Present, and Future] we call 'keeping.' In the Sutra it says, '[We] shall guard and keep what the Buddha has entrusted.' ["Chapter of the Practices of Peaceful Joy"(T.9.36c)] Tendai Daishi says, 'One receives because of faith; one keeps because of recalling.' It also says,
"This Sutra is difficult to keep;
If there is one who keeps it even for short while,
I shall at once rejoice
And the Buddhas shall likewise do so' "
["Chapter of the Jeweled Stupa" 11 (T.9.34b)] (Shijo dono gohenji, STN, v. 1, 894).
"Each person of Japan and so on to the Land of Han, the Yuezhi [India], and the whole of Jambudvipa, regardless of whether they have wisdom or have no wisdom, should uniformly abandon other matters and chant 'Namu Myoho renge kyo'" (Hoon sho, STN, v. 2, 1248).