Study a single sutra by selecting the pada (chapter) and then the sutra (verse).
Source: English translation from Light on the Yoga Sutras of Patanjali (B.K.S. Iyengar)
According to our good, bad or mixed actions, the quality of our life, its span, and the nature of birth are experienced as being pleasant or painful.
Source: English translation from The Heart of Yoga (T.K.V. Desikachar)
The consequences of an action will be painful or beneficial depending on whether the obstacles were present in the concept or implementation of the action.
Source: English translation of the Yoga Sutras of Patanjali (Swami Jnaneshvara Bharati)
Because of having the nature of merits or demerits (virtue or vice), these three (birth, span of life, and experiences) may be experienced as either pleasure or pain.