pravrttam ca nivrttam ca
dvi-vidham karma vaidikam
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
According to the Vedas, there are two kinds of activities — pravrtti and nivrtti. Pravrtti activities involve raising oneself from a lower to a higher condition of materialistic life, whereas nivrtti means the cessation of material desire. Through pravrtti activities one suffers from material entanglement, but by nivrtti activities one is purified and becomes fit to enjoy eternal, blissful life.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As confirmed in Bhagavad-gita (16.7), pravrttim ca nivrttim ca jana na vidur asurah: the asuras, nondevotees, cannot distinguish between pravrtti and nivrtti. Whatever they like they do. Such persons think themselves independent of the strong material nature, and therefore they are irresponsible and do not care to act piously. Indeed, they do not distinguish between pious and impious activity. Bhakti, of course, does not depend on pious or impious activity. As stated in Srimad-Bhagavatam (1.2.6):
sa vai pumsam paro dharmo
yato bhaktir adhoksaje
“The supreme occupation [dharma] for all humanity is that by which men can attain to loving devotional service unto the transcendent Lord. Such devotional service must be unmotivated and uninterrupted in order to completely satisfy the self.” Nonetheless, those who act piously have a better chance to become devotees. As Krsna says in Bhagavad-gita (7.16), catur-vidha bhajante mam janah sukrtino ’rjuna: “O Arjuna, four kinds of pious men render devotional service unto Me.” One who takes to devotional service, even with some material motive, is considered pious, and because he has come to Krsna, he will gradually come to the stage of bhakti. Then, like Dhruva Maharaja, he will refuse to accept any material benediction from the Lord (svamin krtartho ’smi varam na yace). Therefore, even if one is materially inclined, one may take to the shelter of the lotus feet of Krsna and Balarama, or Gaura and Nitai, so that he will very soon be purified of all material desires (ksipram bhavati dharmatma sasvac chantim nigacchati). As soon as one is freed from inclinations toward pious and impious activities, he becomes a perfect candidate for returning home, back to Godhead.