A bhikkhu endures sharp, severe, and painful bodily sensations caused by the results of past actions, while remaining mindful and fully aware, untroubled by the experience.
Kammavipākaja sutta - Caused By The Results Of One's Actions
Thus have I heard - At one time, the Blessed One was dwelling in Sāvatthi, in Jeta's Grove, Anāthapiṇḍika's park. Now, at that time, a certain bhikkhu was sitting not far from the Blessed One, having folded his legs in a cross-legged sitting position and aligning his body in an upright posture. Enduring sharp, severe, and painful bodily sensations that were caused by the results of past actions, he remained mindful and fully aware, untroubled by the experience.
The Blessed One saw that bhikkhu sitting not far away, having folded his legs in a cross-legged sitting position, aligning his body upright, and enduring sharp, severe, and painful bodily sensations caused by the results of past actions, while remaining mindful and fully aware, untroubled by the experience.
Then, understanding the significance of this, the Blessed One at that time expressed this inspired utterance:
"For the bhikkhu who has abandoned all actions, shaking off the dust of past deeds; Steady and free from 'mine', such a one, has no need to complain to anyone."