I have heard that on one occasion Ven. Sariputta was staying near Rajagaha in the Bamboo Grove, the Squirrels' Feeding Sanctuary. There he said to the monks, "This Unbinding is pleasant, friends. This Unbinding is pleasant."

When this was said, Ven. Udayin said to Ven. Sariputta, "But what is the pleasure here, my friend, where there is nothing felt?"

"Just that is the pleasure here, my friend: where there is nothing felt. There are these five strings of sensuality. Which five? Forms cognizable via the eye — agreeable, pleasing, charming, endearing, fostering desire, enticing; sounds cognizable via the ear... smells cognizable via the nose... tastes cognizable via the tongue... tactile sensations cognizable via the body — agreeable, pleasing, charming, endearing, fostering desire, enticing. Whatever pleasure or joy arises in dependence on these five strings of sensuality, that is sensual pleasure.

"Now there is the case where a monk — quite withdrawn from sensuality, withdrawn from unskillful qualities — enters & remains in the first jhana: rapture & pleasure born from withdrawal, accompanied by directed thought & evaluation. If, as he remains there, he is beset with attention to perceptions dealing with sensuality, that is an affliction for him. Just as pain arises as an affliction in a healthy person for his affliction, even so the attention to perceptions dealing with sensuality that beset the monk is an affliction for him. Now, the Blessed One has said that whatever is an affliction is stress. So by this line of reasoning it may be known how Unbinding is pleasant.

"Furthermore, there is the case where a monk, with the stilling of directed thoughts & evaluations, enters & remains in the second jhana: rapture & pleasure born of composure, unification of awareness free from directed thought & evaluation — internal assurance. If, as he remains there, he is beset with attention to perceptions dealing with directed thought, that is an affliction for him...

"Furthermore, there is the case where a monk, with the fading of rapture, he remains equanimous, mindful, & alert, and senses pleasure with the body. He enters & remains in the third jhana, of which the Noble Ones declare, 'Equanimous & mindful, he has a pleasant abiding.' If, as he remains there, he is beset with attention to perceptions dealing with rapture, that is an affliction for him...

"Furthermore, there is the case where a monk, with the abandoning of pleasure & stress — as with the earlier disappearance of elation & distress — enters & remains in the fourth jhana: purity of equanimity & mindfulness, neither-pleasure-nor-pain. If, as he remains there, he is beset with attention to perceptions dealing with equanimity, that is an affliction for him...

"Furthermore, there is the case where a monk, with the complete transcending of perceptions of [physical] form, with the disappearance of perceptions of resistance, and not heeding perceptions of diversity, [perceiving,] 'Infinite space,' enters & remains in the dimension of the infinitude of space. If, as he remains there, he is beset with attention to perceptions dealing with form, that is an affliction for him...

"Furthermore, there is the case where a monk, with the complete transcending of the dimension of the infinitude of space, [perceiving,] 'Infinite consciousness,' enters & remains in the dimension of the infinitude of consciousness. If, as he remains there, he is beset with attention to perceptions dealing with the dimension of the infinitude of space, that is an affliction for him...

"Furthermore, there is the case where a monk, with the complete transcending of the dimension of the infinitude of consciousness, [perceiving,] 'There is nothing,' enters & remains in the dimension of nothingness. If, as he remains there, he is beset with attention to perceptions dealing with the dimension of the infinitude of consciousness, that is an affliction for him...

"Furthermore, there is the case where a monk, with the complete transcending of the dimension of nothingness, enters & remains in the dimension of neither perception nor non-perception. If, as he remains there, he is beset with attention to perceptions dealing with the dimension of nothingness, that is an affliction for him. Now, the Blessed One has said that whatever is an affliction is stress. So by this line of reasoning it may be known how pleasant Unbinding is.

"Furthermore, there is the case where a monk, with the complete transcending of the dimension of neither perception nor non-perception, enters & remains in the cessation of perception & feeling. And, having seen [that] with discernment, his mental fermentations are completely ended. So by this line of reasoning it may be known how Unbinding is pleasant."