I have heard that on one occasion the Blessed One was staying near Vesali in the Great Wood, at the Gabled Hall. Now on that occasion the Blessed One, with many lines of reasoning, was giving the monks a talk on the unattractiveness [of the body], was speaking in praise of [the perception of] unattractiveness, was speaking in praise of the development of [the perception of] unattractiveness. Then the Blessed One addressed the monks: "Monks, I wish to go into seclusion for half a month. I am not to be approached by anyone at all except for the one who brings almsfood."

"As you say, lord," the monks responded to him. And no one approached the Blessed One except for the one who brought almsfood.

Then the monks — [thinking,] "The Blessed One, with many lines of reasoning, has given a talk on the unattractiveness [of the body], has spoken in praise of [the perception of] unattractiveness, has spoken in praise of the development of [the perception of] unattractiveness" — remained committed to the development of [the perception of] unattractiveness in many modes & manners. They — ashamed, repelled, & disgusted with this body — sought for an assassin. In one day, ten monks took the knife. In one day, twenty monks took the knife. In one day, thirty monks took the knife.

Then the Blessed One, emerging from his seclusion after half a month's time, said to Ven. Ananda, "Ananda, why does the community of monks seem so depleted?"

"Because, lord, the Blessed One, with many lines of reasoning, gave the monks a talk on the unattractiveness [of the body], spoke in praise of [the perception of] unattractiveness, spoke in praise of the development of [the perception of] unattractiveness. The monks — [thinking,] 'The Blessed One, with many lines of reasoning, has given a talk on the unattractiveness [of the body], has spoken in praise of [the perception of] unattractiveness, has spoken in praise of the development of [the perception of] unattractiveness' — remained committed to the development of [the perception of] unattractiveness in many modes & manners. They — ashamed, repelled, & disgusted with this body — sought for an assassin. In one day, ten monks took the knife. In one day, twenty monks took the knife. In one day, thirty monks took the knife. It would be good, lord, if the Blessed One would explain another method so that this community of monks might be established in gnosis."

"In that case, Ananda, gather in the assembly hall all the monks who live in dependence on Vesali."

"As you say, lord," Ven. Ananda responded. When he had gathered in the assembly hall all the monks who lived in dependence on Vesali, he went to the Blessed One and said, "The community of monks is gathered, lord. Now is the time to do as the Blessed One sees fit."

Then the Blessed One went to the assembly hall and sat down on a seat made ready. As he was sitting there, he addressed the monks: "Monks, this concentration through mindfulness of in-&-out breathing, when developed & pursued, is both peaceful & exquisite, a refreshing & pleasant abiding that immediately disperses & allays any evil, unskillful [mental] qualities that have arisen. Just as when, in the last month of the hot season, a great rain-cloud out of season immediately disperses & allays the dust & dirt that have been stirred up, in the same way this concentration through mindfulness of in-&-out breathing, when developed & pursued, is both peaceful & exquisite, a refreshing & pleasant abiding that immediately disperses & allays any evil, unskillful [mental] qualities that have arisen.

"And how is concentration through mindfulness of in-&-out breathing developed & pursued so as to be both peaceful & exquisite, a refreshing & pleasant abiding that immediately disperses & allays any evil, unskillful [mental] qualities that have arisen?

"There is the case where a monk, having gone to the wilderness, to the shade of a tree, or to an empty building, sits down folding his legs crosswise, holding his body erect, and setting mindfulness to the fore. Always mindful, he breathes in; mindful he breathes out.

"[1] Breathing in long, he discerns, 'I am breathing in long'; or breathing out long, he discerns, 'I am breathing out long.' [2] Or breathing in short, he discerns, 'I am breathing in short'; or breathing out short, he discerns, 'I am breathing out short.' [3] He trains himself, 'I will breathe in sensitive to the entire body.' He trains himself, 'I will breathe out sensitive to the entire body.' [4] He trains himself, 'I will breathe in calming bodily fabrication.' He trains himself, 'I will breathe out calming bodily fabrication.'

"[5] He trains himself, 'I will breathe in sensitive to rapture.' He trains himself, 'I will breathe out sensitive to rapture.' [6] He trains himself, 'I will breathe in sensitive to pleasure.' He trains himself, 'I will breathe out sensitive to pleasure.' [7] He trains himself, 'I will breathe in sensitive to mental fabrication [feeling & perception].' He trains himself, 'I will breathe out sensitive to mental fabrication.' [8] He trains himself, 'I will breathe in calming mental fabrication.' He trains himself, 'I will breathe out calming mental fabrication.'

"[9] He trains himself, 'I will breathe in sensitive to the mind.' He trains himself, 'I will breathe out sensitive to the mind.' [10] He trains himself, 'I will breathe in gladdening the mind.' He trains himself, 'I will breathe out gladdening the mind.' [11] He trains himself, 'I will breathe in steadying the mind.' He trains himself, 'I will breathe out steadying the mind. [12] He trains himself, 'I will breathe in releasing the mind.' He trains himself, 'I will breathe out releasing the mind.'

"[13] He trains himself, 'I will breathe in focusing on inconstancy.' He trains himself, 'I will breathe out focusing on inconstancy.' [14] He trains himself, 'I will breathe in focusing on dispassion [literally, fading].' He trains himself, 'I will breathe out focusing on dispassion.' [15] He trains himself, 'I will breathe in focusing on cessation.' He trains himself, 'I will breathe out focusing on cessation.' [16] He trains himself, 'I will breathe in focusing on relinquishment.' He trains himself, 'I will breathe out focusing on relinquishment.'

"This is how concentration through mindfulness of in-&-out breathing is developed & pursued so as to be both peaceful & exquisite, a refreshing & pleasant abiding that immediately disperses & allays any evil, unskillful [mental] qualities that have arisen."