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.‘
Often, you’ll find that Nirvana (also called Nibbana) is translated as “extinction” – like dead, no more. So people think that when the Buddha entered Nirvana upon the passing of his physical body, he too is dead, no more.
The often used simile to describe Nirvana is like a flame gone out – extinct. But people misunderstand this simile.
The flame symbolizes the afflictions (check out the Fire Sermon), which are like fires which burn you up. So what gets extinct in Nirvana are the fires of the 3 poisons – greed, hatred and delusion. Suffering is also extinguished in Nirvana.
So the air gets consumed by the fire, burning up the oxygen. But when the fire gets extinguished, where has the air gone? Did it go north, south, east or west? And the answer is, it hasn’t gone anywhere – it’s still there. It’s just that the air is no longer being consumed and being burnt off by the fire.
Nibbanam paramam sukham said the Buddha – Nirvana is the highest happiness, the most ultimate bliss. This is how we know that Nirvana is not just a mere extinction and death.
And in the Mahaparinirvana Sutra, the Buddha elaborates more – just because you can no longer see the King, who is enjoying himself secluded in a secret section of his Royal palace – doesn’t mean that the King has died. He’s there in the most blissful of surroundings, enjoying the fruits of enlightenment, the flowers of enlightenment. Now this doesn’t mean that the Buddha is literally there smelling flowers in Nirvana, but he’s more speaking metaphorically to show that the Buddha is experiencing the highest happiness in Nirvana.
Similarly, even though the Buddha’s physical body has passed on, the real Buddha – the Buddha Nature has not died. The Buddha Nature was never born and so, having not been created, it can never be destroyed, it can never die.
In the Diamond Sutra (also called the Vajra Prajna Paramita Sutra), the Buddha says:
If you see me in forms
If you hear me in sounds
You walk a deviant path
And do not see the Tathagata
This means the physical appearance (the form) of the Buddha is not the real Buddha. When the people heard the Buddha talking – those were just sounds the physical body of the Buddha made – but that’s not the real Buddha. So don’t mistake the real Tathagata – to be his just his physical body – the real Buddha is beyond his mere physical body, because the physical body is destructible and so, is not ultimate. The real Buddha is indestructible, Deathless – can not die.
Anything that is destructible is not ultimate because it is subject to the changes and ravages of impermanence. Therefore anything that can be destroyed can not be ultimate.
Even in material things, we can observe this. If you buy something and it breaks not long after you buy it – you’d think that that it was poor quality. On the other hand, if something lasts and lasts and lasts and keeps functioning like new, even after years of use – you’d say that it is of excellent quality.
Same principle here. If something is of the nature to break – sooner or later it’s going to break – therefore it’s not ultimate.