From Contemplation of Feeling: The Discourse-grouping on the Feelings (WH 303), translated from the Pali by Nyanaponika Thera (Kandy: Buddhist Publication Society, 1983).
"When an untaught worldling is touched by a painful (bodily) feeling, he worries and grieves, he laments, beats his breast, weeps and is distraught. He thus experiences two kinds of feelings, a bodily and a mental feeling. It is as if a man were pierced by a dart and, following the first piercing, he is hit by a second dart. So that person will experience feelings caused by two darts. It is similar with an untaught worldling: when touched by a painful (bodily) feeling, he worries and grieves, he laments, beats his breast, weeps and is distraught. So he experiences two kinds of feeling: a bodily and a mental feeling.
"Having been touched by that painful feeling, he resists (and resents) it. Then in him who so resists (and resents) that painful feeling, an underlying tendency of resistance against that painful feeling comes to underlie (his mind). Under the impact of that painful feeling he then proceeds to enjoy sensual happiness. And why does he do so? An untaught worldling, O monks, does not know of any other escape from painful feelings except the enjoyment of sensual happiness. Then in him who enjoys sensual happiness, an underlying tendency to lust for pleasant feelings comes to underlie (his mind). He does not know, according to facts, the arising and ending of these feelings, nor the gratification, the danger and the escape, connected with these feelings. In him who lacks that knowledge, an underlying tendency to ignorance as to neutral feelings comes to underlie (his mind). When he experiences a pleasant feeling, a painful feeling or a neutral feeling, he feels it as one fettered by it. Such a one, O monks, is called an untaught worldling who is fettered by birth, by old age, by death, by sorrow, lamentation, pain, grief and despair. He is fettered by suffering, this I declare.
"But in the case of a well-taught noble disciple, O monks, when he is touched by a painful feeling, he will not worry nor grieve and lament, he will not beat his breast and weep, nor will he be distraught. It is one kind of feeling he experiences, a bodily one, but not a mental feeling. It is as if a man were pierced by a dart, but was not hit by a second dart following the first one. So this person experiences feelings caused by a single dart only. It is similar with a well-taught noble disciple: when touched by a painful feeling, he will no worry nor grieve and lament, he will not beat his breast and weep, nor will he be distraught. He experiences one single feeling, a bodily one.
"Having been touched by that painful feeling, he does not resist (and resent) it. Hence, in him no underlying tendency of resistance against that painful feeling comes to underlie (his mind). Under the impact of that painful feeling he does not proceed to enjoy sensual happiness. And why not? As a well-taught noble disciple he knows of an escape from painful feelings other than by enjoying sensual happiness. Then in him who does not proceed to enjoy sensual happiness, no underlying tendency to lust for pleasant feelings comes to underlie (his mind). He knows, according to facts, the arising and ending of those feelings, and the gratification, the danger and the escape connected with these feelings. In him who knows thus, no underlying tendency to ignorance as to neutral feelings comes to underlie (his mind). When he experiences a pleasant feeling, a painful feeling or a neutral feeling, he feels it as one who is not fettered by it. Such a one, O monks, is called a well-taught noble disciple who is not fettered by birth, by old age, by death, by sorrow, lamentation, pain, grief and despair. He is not fettered to suffering, this I declare.
"This, O monks, is the distinction, the diversity, the difference that exists between a well-taught noble disciple and an untaught worldling."