"Monks, an uninstructed run-of-the-mill person feels feelings of pleasure, feelings of pain, feelings of neither-pleasure-nor-pain. A well-instructed disciple of the noble ones also feels feelings of pleasure, feelings of pain, feelings of neither-pleasure-nor-pain. So what difference, what distinction, what distinguishing factor is there between the well-instructed disciple of the noble ones and the uninstructed run-of-the-mill person?"
"For us, lord, the teachings have the Blessed One as their root, their guide, & their arbitrator. It would be good if the Blessed One himself would explicate the meaning of this statement. Having heard it from the Blessed One, the monks will remember it."
"In that case, monks, listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said, "When touched with a feeling of pain, the uninstructed run-of-the-mill person sorrows, grieves, & laments, beats his breast, becomes distraught. So he feels two pains, physical & mental. Just as if they were to shoot a man with an arrow and, right afterward, were to shoot him with another one, so that he would feel the pains of two arrows; in the same way, when touched with a feeling of pain, the uninstructed run-of-the-mill person sorrows, grieves, & laments, beats his breast, becomes distraught. So he feels two pains, physical & mental.
"As he is touched by that painful feeling, he is resistant. Any resistance-obsession with regard to that painful feeling obsesses him. Touched by that painful feeling, he delights in sensual pleasure. Why is that? Because the uninstructed run-of-the-mill person does not discern any escape from painful feeling aside from sensual pleasure. As he is delighting in sensual pleasure, any passion-obsession with regard to that feeling of pleasure obsesses him. He does not discern, as it actually is present, the origination, passing away, allure, drawback, or escape from that feeling. As he does not discern the origination, passing away, allure, drawback, or escape from that feeling, then any ignorance-obsession with regard to that feeling of neither-pleasure-nor-pain obsesses him.
"Sensing a feeling of pleasure, he senses it as though joined with it. Sensing a feeling of pain, he senses it as though joined with it. Sensing a feeling of neither-pleasure-nor-pain, he senses it as though joined with it. This is called an uninstructed run-of-the-mill person joined with birth, aging, & death; with sorrows, lamentations, pains, distresses, & despairs. He is joined, I tell you, with suffering & stress.
"Now, the well-instructed disciple of the noble ones, when touched with a feeling of pain, does not sorrow, grieve, or lament, does not beat his breast or become distraught. So he feels one pain: physical, but not mental. Just as if they were to shoot a man with an arrow and, right afterward, did not shoot him with another one, so that he would feel the pain of only one arrow. In the same way, when touched with a feeling of pain, the well-instructed disciple of the noble ones does not sorrow, grieve, or lament, does not beat his breast or become distraught. He feels one pain: physical, but not mental.
"As he is touched by that painful feeling, he is not resistant. No resistance-obsession with regard to that painful feeling obsesses him. Touched by that painful feeling, he does not delight in sensual pleasure. Why is that? Because the well-instructed disciple of the noble ones discerns an escape from painful feeling aside from sensual pleasure. As he is not delighting in sensual pleasure, no passion-obsession with regard to that feeling of pleasure obsesses him. He discerns, as it actually is present, the origination, passing away, allure, drawback, and escape from that feeling. As he discerns the origination, passing away, allure, drawback, and escape from that feeling, no ignorance-obsession with regard to that feeling of neither-pleasure-nor-pain obsesses him.
"Sensing a feeling of pleasure, he senses it disjoined from it. Sensing a feeling of pain, he senses it disjoined from it. Sensing a feeling of neither-pleasure-nor-pain, he senses it disjoined from it. This is called a well-instructed disciple of the noble ones disjoined from birth, aging, & death; from sorrows, lamentations, pains, distresses, & despairs. He is disjoined, I tell you, from suffering & stress.
"This is the difference, this the distinction, this the distinguishing factor between the well-instructed disciple of the noble ones and the uninstructed run-of-the-mill person."
See also: SN 1.38; SN 4.13; AN 5.129; Straight from the Heart.