Reading the KYOGYOSHINSHO (212)
“Contemplating true and real [joyful faith], I find there is the one thought-moment. One thought-moment expresses the ultimate brevity of the instant of the realization of [joyful faith] and manifests the vast, inconceivable mind of joyfulness.”
“The word hear in the passage from the [Larger] Sutra means that sentient beings, having heard how the Buddha’s Vow arose – its origin and fulfillment – are altogether free of doubt. This is to hear. Shinjin is shinjin that is directed to beings through the power of the Primal Vow. Joy expresses gladness in body and mind. Even includes both many and few. One thought-moment: because shinjin is free of double-mindedness, one thought-moment is used. It is the mind that is single. The mind that is single is the true cause of [birth in] the pure fulfilled land.”
The doctrine of birth through “one thought-moment of faith” is only [to be found in] Jōdo Shinshū. “One thought-moment of faith” means “Namo Amida Butsu, don’t worry, you are saved just as you are,” while hearing this, “Ah! so happy!” What showed us that we are born [in the Pure Land] through one thought-moment of shinjin and joy is “[as they] hear the Name, realize even one thought-moment of shinjin and joy, they then attain birth” from the passage on the fulfilment of the Primal Vow.
The passage on fulfillment in the last volume of the Larger Sutra is the true spirit of the Eighteenth Vow described by Shaka Nyorai in the first volume. This is the face of Jōdo Shinshū and is also the basis of peace of mind [anjin] in Shinshū.
In the Eighteenth Vow (first volume of the Larger Sutra), the threefold faith (three minds) of “sincere mind, joyful faith, and wish to be born in my land,” shinjin (faith) and the “nembutsu” of “even one thought-moment” (practice), [which are] “faith” and “practice,” have been vowed.
Zendō Daishi [Master Shan-tao] interprets the Eighteenth Vow as saying:
“Sentient beings who say the Name will surely be born (if sentient beings say the Name they will certainly be born [in the Pure Land].)”
The passage on the fulfillment (last volume of the Larger Sutra) of the Primal Vow (Eighteenth Vow) states,
“All sentient beings, as they hear the Name, realize even one thought-moment of shinjin and joy, which is directed to them from Amida’s sincere mind, and aspiring to be born in that land, they then attain birth and dwell in the stage of nonretrogression.” (2)
The text of the Eighteenth Vow reads,
“If, when I attain Buddhahood, sentient beings in the lands of the ten directions who sincerely and joyfully entrust themselves to me, desire to be born in my land, and think of me even ten times should not be born there, may I not attain perfect enlightenment.” (1)
Zendō Daishi interprets the text of the Eighteenth Vow as follows:
“If, when I attain Buddhahood, the sentient beings of the ten quarters say my Name even ten times but do not attain birth, may I not attain the supreme enlightenment. The Buddha is now actually there in the Pure Land, and has attained Buddhahood. Know that the momentous Primal Vow is not in vain, and that when sentient beings say the Name, they unfailingly attain birth.” (3)