In the following quotes, the Buddha speaks of the nature of the Buddha in the realm of nirvanic Liberation (moksha) and how this is not the blotting out or ending of the Buddha - but constitutes his entry into an eternal, immutable, supremely peaceful state (Nirvana).
First, however, the Buddha speaks of the mysterious 'Dharma' - Truth - which is the incomprehensible Reality within which Buddhas live and have their being. The qualities of Dharma seem paradoxical, but that is because the Buddha here is speaking about Dharma from different angles and perspectives:
1) 'How does a bodhisattva-mahasattva [i.e. great Bodhisattva] recollect [anusmrti - i.e. think of, remember, recall] the Dharma? Noble son, a bodhisattva-mahasattva reflects thus, "The Dharma which the Buddhas have taught is most excellent and superlative. Because of this Dharma, even ordinary beings are able to attain the result in the present. This authentic Dharma alone has no time or season. If it is only seen with the Dharma-eye and not with the physical eye, no simile can serve as an analogy for it. It is unborn, unarisen, unabiding, not perishing, without beginning, without end, unconditioned [asamskrta - uncompounded, not assembled from constituent parts] and immeasurable. It provides a dwelling for those who are homeless, a refuge for those without a refuge, light for those without light; it enables those who have not reached the far shore [of Nirvana] to reach it; it is unimpeded fragrance for places without fragrance, it displays what cannot be seen, it is unwavering / imperturbable, it does not change, it is not long, it is not short. Although it is utterly divorced from happiness [i.e. worldly, samsaric, sense-based happiness], it is the ultimate, subtle bliss of security. Separated from matter [rupa - the physical body or physical form], it is not matter, and yet it is matter. And so forth [regarding the other skandhas] down to separated from consciousness, it is not consciousness, and yet it is consciousness. Separated from karmic action, it is not karmic action, separated from the fetters [samyojana], it is not a fetter, separated from substantial things [vastu], it is not a substantial thing, and yet it is a substantial thing. Separated from perceptual bases [dhatu], it is not a perceptual base, and yet it is a perceptual base. Separated from existents [bhava - i.e. things which exist samsarically, gripped by change and eventual death], it is not an existent, and yet it is an existent. Separated from perceptual spheres [ayatana], it is not a perceptual sphere, and yet it is a perceptual sphere. Separated from causes, it is not a cause, and yet it is a cause. Separated from results, it is not a result, and yet it is a result. It is not false and it is not real [satya]. Though it is separated from all that is real [in a worldly sense], yet it is real. It does not arise and it does not cease. Though utterly separated from arising and ceasing, yet it is cessation. It does not have attributes nor does it not have attributes. Though separated from all attributes, yet it does have attributes. It is not teaching nor is it not teaching, and yet it is a teacher. It is not fearful anxiety nor is it security, but separated from all fearful anxiety, it is security. It is not patient acceptance [ksanti - patient endurance] nor is it not patience acceptance, but utterly separated from what is not patient acceptance, it is patient acceptance. It is not tranquility [samatha] nor is it not tranquility, but separated from all tranquility, it is tranquility, the pinnacle of all dharmas. It can utterly eradicate all afflictions [the kleshas - negative states of mind and behaviour]; it is totally pure [vyavadana]; it is devoid of perceptual attributes [nimitta - i.e. generally, outward signs, characteristics or features], and it is liberated from perceptual attributes. It is the ultimate dwelling-place of countless beings. It extinguishes all the fires of samsara. It is the abode where the Buddhas disport themselves. It is permanent [nitya - eternal] and unchanging [aviparinama]. This is how a bodhisattva recollects the Dharma.'
2) 'For example, just as when heated iron is struck and sparks fly out,
they scatter and soon disappear, nobody knows where;
One who has attained full Liberation is also thus,
having crossed over desire, the mire of samsaric existence,
he attains the unmoving state: nobody knows where he has gone.
How is the Tathagata deemed to be a permanently abiding entity / element [dharma]?Any such objection that somebody may raise is a perverse objection. Kashyapa, you should not give rise to this idea, namely that the nature of the Tathagata perishes. Kashyapa, the extinction of the afflictions is not termed "a material thing" [vastu / dravya = substance]. Why is that? Because it is eternal and hence is permanent. The peace of this state is supreme; it extinguishes [all] perceptual attributes [nimitta] without remainder. The purity of this state is permanently abiding, without retrogression. Therefore Nirvana is said to be [i.e. is stated by the Buddha to be] permanently abiding. The Tathagata is also thus, permanently abiding without change. "Sparks fly out" signifies the afflictions [klesha]. "They scatter and soon disappear, nobody knows where" signifies that the Tathagatas have extinguished the afflictions and do not dwell in any of the five modes of [samsaric] existence [gati]. Therefore, the Tathagata is a permanently abiding element / entity, without any alteration / mutation. Moreover, Kashyapa, that which the Buddhas treat as their teacher is the Dharma, therefore the Tathagata should be honoured and worshipped. Since the Dharma is permanent, the Buddhas are also permanent.'
3) The Buddha said to Kashyapa, 'You should not now say that the Tathagata is impermanent. Why? The Tathagata is permanent. Noble son, just as there is ash when burning wood has been consumed, when the afflictions [klesha] have been extinguished, there is Nirvana. Such examples as shredded cloth, a severed head, a smashed jar are also similar. Such things each have a name: "shredded cloth", "severed head" and "smashed jar". Kashyapa, though the iron which has been cooled can be reheated; the Tathagata is not thus, for once he has severed the afflictions, he is utterly calmed [shita = cool]; the burning fire of the afflictions will not again arise. Kashyapa, you should know that the countless beings are like that iron. I burn away all the afflictions of those beings with the burning fire of unsullied Awareness [jnana - gnosis].'
Kashyapa spoke again, 'Excellent, excellent! I now truly understand what the Tathagata has explained regarding the permanence of Buddhas.'
The Buddha said to Kashyapa, 'It is like, for example, a sacred king who dwells in the inner palace who may on one occasion dwell in a rear garden, enjoying himself. Although the king is not there amongst his concubines, one does not say that the king has died. Noble son, the Tathagata is also like this. Although he is not visible in the realm of Jambudvipa [i.e. our terrestrial world], having entered Nirvana, one does not say that he is impermanent. The Tathagata has extricated himself from the countless afflictions and entered into Nirvana, the abode of bliss, wandering among the flowers of Enlightenment, disporting and enjoying the pleasures.'
[Comment by Dr. Tony Page: here the lie is given to the idea that a Buddha in Nirvana is merely nothingness or a mental, vacuous blank. In fact, Nirvana is both inner Reality and 'outer' realm [the 'abode of bliss'], wherein Buddhas can 'disport and enjoy the pleasures'. This is far from being a nihilistic teaching!].
4) 'That which is Liberation is ungenerated (ajâta) and hence it is utterly separated from all bonds. It is not generated in the way that a child is generated from the union of his parents, for Liberation abides in its own domain (viṣaya). ‘Ungenerated’ is thus: just as the quintessence of ghee naturally abides in its own intrinsic state so also does the Tathâgata not arise from the sexual union of his parents, though the Tathâgata displays [birth from] his parents for the sake of those to be trained. That which is Liberation is the Tathâgata, because he arises without arising. For example, if we plant the seeds of lentils (mudga) or beans (mâṣa) in February, the summer months or October, they give forth sprouts, but Liberation is not like that. That which does not arise is Liberation. That which is Liberation is the Tathâgata and unarisen. The Tathâgata is entirely non-arisen and one cannot discern any coming into being and ceasing to be as with sprouts. The Tathâgata is intrinsically non-arisen.' [From the chapter, 'The Four Methods of Teaching', of the Tibetan version of the MPNS].
[Note from Dr. Tony Page: It is key to an understanding of the nature of Nirvana (i.e., Liberation and the Buddha, which are one) that it is not begotten or generated. It is not the final result of myriads of causes. It is not like a seed that puts out buds and grows into a plant: that is specifically denied here - although numerous latter-day commentators on Buddhism will wrong-headedly claim precisely the opposite to what the Buddha declares. Liberation dwells in its own realm. That realm already exists, but it is a world as yet unknown to us. It is not created - it is already here (within us). It is like the ghee which is deemed to be an essence already present, but unseen, within the milk. It is merely a question of recognising that hidden Reality and entering into it. Once that has been accomplished, there is no end to such Liberation. It is eternal. And it is always linked in to a person - the true personhood of Buddha: not an ego, not a bundle of shifting skandhas, but the mysterious THAT-ness (tathata) underlying all existence].
5) 'Kaundinya, rupa [form, body, matter] is suffering, but through the elimination of this rupa one attains Liberation, the rupa [body, form] of tranquil bliss. Vedana [feeling], samjna [perception, ideation], samskara [mental activities, including volition] and vijnana [consciousness] are also likewise. Kaundinya, rupa is empty, but through the elimination of empty rupa, one attains Liberation, non-empty rupa [form, body]. Vedana, samjna, samskara, and vijnana are also likewise. Kaundinya, rupa is anatman [not-Self], but through the elimination of this rupa, one attains Liberation, the rupa [form, body] of the True Self. Vedana, samjna, samskara and vijnana are also likewise.' [Yamamoto/Page edition, Vol. 11, p. 28].
[Comment by Dr. Tony Page: This is an extremely significant passage, yet (as far as I am aware) as good as never quoted in Western books on Buddhism. It reveals that the Buddha himself in Liberation does possess skandhas, but that these are transcendental ones (lokottara - beyond the world). These are not samsaric skandhas, which are conducive to pain and suffering, but are instead liberated and liberating Buddhic skandhas. Very few Western Buddhists are aware of this fact - because it has been systematically withheld from them by a Buddhist orthodoxy which wishes to promulgate the notion that Nirvana is total and utter 'non-Self'.
Why does this revelation of the Buddha's skandhas instil so much fear in Buddhist nihilists? The reason is that it indicates that personhood continues in Nirvana - albeit of an order, nature and magnitude which our worldly minds cannot conceive. That is why Buddhas can converse with each other - as in the Lotus Sutra - and that is why the Nirvana Sutra, again and again, stresses that the wondrous qualities associated with Parinirvana inhere in the person and being of the Buddha. They are not free-floating. They are embodied in a transcendental being].
[Tentative note from Stephen Hodge: 'the wording here [in the quote] is very similar in parts to the Heart Sutra - a deliberate allusion, I think, with a corrective intention'].
6) The Buddha gives an important explanation of the Buddha Nature:
'You have asked what the Buddha-dhatu [Buddha Nature, Buddha Essence] is, so listen with sincerity, listen with sincerity, I shall analyse and elucidate it for your sake. Nobly-born son, the Buddha-dhatu is termed "ultimate emptiness" [paramartha-sunyata], and ultimate emptiness is termed Awareness [jnana - gnosis]. So-called emptiness is neither viewed as emptiness nor as non-emptiness. The wise perceive emptiness and non-emptiness, the permanent and the impermanent, suffering and bliss, Self and non-Self. The empty is the totality of samsara and the non-empty is Great Nirvana [and so forth down to], non-Self is samsara, and the Self is Great Nirvana. To perceive the emptiness of everything and not to perceive non-emptiness is not termed the Middle Way [and so forth down to], to perceive the non-Self of everything, and not to perceive the Self is not termed the Middle Way. The Middle Way is termed the Buddha-dhatu. For this reason, the Buddha-dhatu is eternal and unchanging. Because beings are enveloped in ignorance, they are unable to perceive it. Sravakas and pratyekabuddhas [i.e. relatively high-level spiritual aspirants, but lower than full Buddhas] perceive the emptiness of everything, but do not perceive the non-emptiness [and so forth down to], they perceive the absence of self [i.e. non-Self] in all things, but do not perceive the Self. For this reason, they do not attain the ultimate emptiness. Because they do not attain the supreme emptiness, they do not walk the Middle Way. Because they lack the Middle Way, they do not perceive the Buddha-dhatu.'
[Notes from Dr. Tony Page: this is one of the most important passages in the whole Mahaparinirvana Sutra. It is often quoted by nihilistically inclined commentators - but in radically truncated form. They usually give their readers only the first part: 'The Buddha-dhatu is ultimate emptiness'. They then generally excise all that follows. What are they frightened of? What are they trying to suppress and censor? They are frightened of the fact that emptiness is here clearly defined - but not defined as 'causes and conditions', 'conditionality', pratitya-samutpada, or 'lack of inherent existence', which are so beloved of nihilistic commentators. Instead, emptiness is defined as Awareness, or Gnosis, or Knowing (jnana) - and for there to be Knowing, there must be a Knower (gnosis is not some free-floating blankness drifting around space). Who is that Knower? The Buddha. The term 'Budd-ha' actually means: 'The One who Knows / The One who is Awake'. This terrifies nihilists, because it brings personhood (of an incomprehensible, supernal kind) back into the equation - and personhood is something the nihilists cannot brook for one second.
The second reason the nihilists erase the balance of the quote is that it contains the damning (for them) declaration that, not only is there Self (which the entire sutra unequivocally teaches to be the Eternal Buddha), but that if one only sees non-Self and impermanence in everything, one is not traversing the Middle Path and will consequently not gain the liberatory vision of the Buddha-dhatu - and therewith secure entry into Great Nirvana. What is Great Nirvana? It is the Self. What is the Self? It is the Buddha - unbegotten, unblemished, unharmed, unaging, and undying: highest transcendental Reality. This message is poison to the nihilists - but to sincere, Buddha-respecting and open-hearted spiritual seekers after Truth, it is the most delicious spiritual nutriment. It is ambrosia (as the Buddha elsewhere in the sutra terms it). It is nothing less than the Authentic Dharma.]