大乘起信論廣釋卷第三．四．五 3.49

3.49

[Treatise:] Therefore the sūtras [… down to …] because there is nothing that can be seen.
[Commentary:] This is citing scriptural evidence. Because defilement and purity are identical in tathatā as stated before, sūtras rely on this meaning to state that all sentient beings are originally in nirvāṇa, attain bodhi, and so forth. Although stated generally like this, to distinguish them specifically: because fundamental and derivative non-awakening are identical to tathatā, sentient beings are immediately in nirvāṇa and do not undergo further cessation; because original and initial awakenings are identical to tathatā, bodhi is also fundamentally existent, not newly attained. Therefore, this nirvāṇa does not await cultivation of a revealing cause before being realized; hence it says: 'not a characteristic that can be cultivated.' This bodhi does not await a productive cause before being produced; hence it says: 'not a characteristic that can be produced.' Since these two fruits are fundamentally existent by nature and not further attained, it says: 'ultimately unattainable.' From 'also without' onward is still the sūtra text; to dispel doubts and objections, the treatise cites it in full. That is to say, there is an objection saying: If all sentient beings are already in nirvāṇa, etc., why do they not manifest physical marks of the saṃbhogakāya, nirmāṇakāya, etc., like the Buddha? Therefore, this first clause explains this meaning, saying: The substance of dharmatā itself is not visible as physical form; how could it further manifest physical marks? Hence it says: 'also without visible physical marks.' Again, there is a doubt saying: If, because dharmatā is not visible as physical form, it does not manifest form, why do the Buddhas manifest physical marks? Therefore, the clauses below explain this meaning, saying: That those [sentient beings] see the various forms of the Buddhas is entirely manifested through variations conforming to sentient beings' defiled, illusory minds; it does not mean the form of the nature of non-empty cognition, because the true substance of cognition cannot be seen. Hence it says: 'yet there is the seeing of form,' and so forth. 'Does not mean the form of the non-empty nature of cognition': if this text is interpreted in reverse, it contradicts the text.