Sn 3.12
Dvayatanupassana Sutta: The Noble One's Happiness
(excerpt)
translated from the Pali by
John D. Ireland
Alternate translations: Olendzki (excerpt) | Thanissaro

...

"See how the world together with the devas has self-conceit for what is not-self. Enclosed by mind-and-body it imagines, 'This is real.' Whatever they imagine it to be, it is quite different from that. It is unreal, of a false nature and perishable. Nibbana, not false in nature, that the Noble Ones[1] know as true. Indeed, by the penetration of the true, they are completely stilled and realize final deliverance.

"Forms, sounds, tastes, scents, bodily contacts and ideas which are agreeable, pleasant and charming, all these, while they last, are deemed to be happiness by the world with its devas. But when they cease that is agreed by all to be unsatisfactory. By the Noble Ones, the cessation of the existing body[2] is seen as happiness. This is the reverse of the outlook of the whole world.

"What others call happiness, that the Noble Ones declare to be suffering. What others call suffering, that the Noble Ones have found to be happiness. See how difficult it is to understand the Dhamma! Herein those without insight have completely gone astray. For those under the veil (of ignorance) it is obscured, for those who cannot see it is utter darkness. But for the good and the wise it is as obvious as the light for those who can see. Even though close to it, the witless who do not know the Dhamma, do not comprehend it.

"By those overcome by attachment to existence, those who drift with the stream of existence, those in the realm of Mara, this Dhamma is not properly understood. Who other than the Noble Ones, are fit to fully understand that state, by perfect knowledge of which they realize final deliverance, free from defilements?"[3]

...

Notes

1.
The Noble Ones or ariya are the Buddhas and their disciples.
2.
The "existing body" (sakkaya) is a term for the five aggregates as objects of grasping.
3.
Anusava; the defilements or asava, literally "out-flows," are dissipations of energy in the form of sensual desire, becoming (the perpetuation of existence), views and ignorance and are the same as the four "floods" mentioned earlier. One who has destroyed the defilements (khinasava) is another name for an arahant or Perfected One.