Considering sacrifices and works of merit as the supreme, the completely confused know no other higher good. Having enjoyed at the summit of heaven the fruits of their good actions, they return to this world or to an inferior one.

The cyclical nature of karmic results: even elevated worlds are temporary.

Iṣṭāpūrtam — sacrifices and works of merit. The rituals (iṣṭa) and public works (pūrta), both accumulators of merit.

Manyamānā variṣṭham — considering as supreme. The ultimate confusion: taking the temporal for the eternal.

Pramūḍhāḥ — completely confused. The intensive suffix indicates depth of ignorance.

Nākasya pṛṣṭhe — at the summit of heaven. The highest world attainable through ritual.

Anubhūtvā — having enjoyed. Pleasure in higher worlds exhausts accumulated merit.

Imaṃ lokaṃ hīnataraṃ vā — this world or an inferior one. The inevitable return once merit is spent.

Without liberating knowledge, the cycle continues. The yogī seeks what never exhausts.