寶王三昧念佛直指 2.18

2.18

其有身心之力不及，於此法行不能具修。若欲但修五時者，當止日中時。欲修四時者，又止夜中時。欲修三時者，又再止日後時。若欲但修二時者，惟在早晚之間也。又行雖隨意而立，立定之後不許改易，但可增修、不可退減，縱有病緣官事亦當想念。豈可隨或勤怠，或興或廢、朝立暮改，使其正行不純一也。今欲修此道者，必先取彼念佛法則及淨土經懺呪等前後排布，如意多少安頓諦當，再三審實我能行不？譬如有人浮身渡水，察水遠近，不致疲絕而乃渡之。行人亦爾，觀自勤怠、觀法廣略而乃取之。不當趁一時之勇而立、即時而廢。又不可別有誦持，心不專注。如人發箭，心一則中；念佛法門亦復如是，若能行純心一，應念得生，遊戲極樂。於一念中所獲功德，豈易量哉？

If someone's physical and mental strength is insufficient to fully cultivate this Dharma practice, should they wish to cultivate only five periods, they should cease during the noon period. If they wish to cultivate four periods, they should also cease during the midnight period. If they wish to cultivate three periods, they should further cease during the late afternoon period. If they wish to cultivate only two periods, it should be solely between morning and evening. Furthermore, although the practice is established according to one's capacity, once established it is not permitted to change it: one may only increase practice, not retreat or reduce it. Even if there are circumstances of illness or official duties, one should still keep it in mind. How could one follow diligence or indolence, now undertaking and now abandoning, establishing in the morning and changing in the evening, making one's proper practice ununified? Now, whoever wishes to cultivate this Way must first take those rules of buddha-mindfulness and the Pure Land sūtras, penitences, and dhāraṇīs, arrange them in order, properly settle whether more or less according to their inclination, and repeatedly examine in truth: Can I carry this out? It is like a person swimming across the water who examines the distance of the water so that they will not reach exhaustion, and only then crosses it. The practitioner is also like this: observing one's own diligence and indolence, and observing the extensive or abbreviated nature of the Dharma, one only then adopts it. One must not establish it by seizing upon momentary courage, only to abandon it immediately. Furthermore, one must not engage in other recitations so that the mind lacks single-minded focus. It is like a person shooting an arrow: if the mind is unified, it hits the target; the Dharma door of buddha-mindfulness is also like this. If the practice can be pure and the mind unified, in accordance with the thought one attains rebirth and roams at play in Sukhāvatī. How could the merit attained in a single thought be easily measured?