yadā - when; karmasu - in duties; kāmyeṣu - based on selfish desire; bhaktiḥ - devotion; yaśasi - in honor; dehinām - of the embodied souls; tadā - then; tretā - the age of Tretā; rajaḥ-vṛttiḥ - predominated by activities in the mode of passion; iti - thus; jānīhi - you should understand; buddhi-man - O intelligent King Parīkṣit.

O most intelligent one, when the conditioned souls are devoted to their duties but have ulterior motives and seek personal prestige, you should understand such a situation to be the age of Tretā, in which the functions of passion are prominent.