Yoga Sutra 2.14 their fruits are joy and suffering caused by virtue and sin
Sūtra II.14
Their fruits are joy and suffering caused by virtue and sin
The birth, life span, and experience of which virtue is the causal agent are happy fruits; those of which sin is the causal agent are painful. What is inherently adverse is pain, so for the yogin even at the time of pleasure there is only pain, because even pleasure is adverse to the yogin.
Karma-stock has been further explained as: due to be felt in a present life, and due to be felt in future lives. Of it there are three fruitions: birth, life span, and experience. Their fruits are joy and suffering, caused by virtue and sin. Joy is happiness, suffering is pain. This pair of joy and suffering are the fruits of those (actions). Virtue and sin are also a pair, and these two are the respective causes. The causality of the two is a fact and so it is said that the causes are virtue and sin. The birth, life span, and experience of which virtue is the causal agent are happy fruits; those of which sin is the causal agent are painful. What is inherently adverse is pain, so for the yogin even at the time of pleasure there is only pain, because even pleasure is adverse to the yogin.
How so? The answer is: