Bg. 9.21

ते तं भुक्त्वा स्वर्गलोकं विशालं
क्षीणे पुण्ये मर्त्यलोकं विशन्ति ।
एवं त्रयीधर्ममनुप्रपन्ना
गतागतं कामकामा लभन्ते ॥२१॥

Text

te taṁ bhuktvā svarga-lokaṁ viśālaṁ
kṣīṇe puṇye martya-lokaṁ viśanti
evaṁ trayī-dharmam anuprapannā
gatāgataṁ kāma-kāmā labhante

Synonyms

te—they; tam—that; bhuktvā—enjoying; svarga-lokam—heaven; visalam—vast; kṣīṇe—being exhausted; puṇye—merits; martya-lokam—mortal earth; visanti—fall down; evam—thus; trayī—three Vedas; dharmam—doctrines; anuprapannāḥ—following; gata-agatam—death and birth; kama-kamah—desiring sense enjoyments; labhante—attain. 

Translation

When they have thus enjoyed heavenly sense pleasure, they return to this mortal planet again. Thus, through the Vedic principles, they achieve only flickering happiness. 

Purport

One who is promoted to those higher planetary systems enjoys a longer duration of life and better facilities for sense enjoyment, yet one is not allowed to stay there forever. One is again sent back to this earthly planet upon finishing the resultant fruits of pious activities. He who has not attained perfection of knowledge, as indicated in the Vedānta-sūtra (janmādy asya yataḥ), or, in other words, he who fails to understand Kṛṣṇa, the cause of all causes, becomes baffled in achieving the ultimate goal of life and is thus subjected to the routine of being promoted to the higher planets and then again coming down, as if situated on a ferris wheel which sometimes goes up and sometimes comes down. The purport is that instead of being elevated to the spiritual world where there is no longer any possibility of coming down, one simply revolves in the cycle of birth and death on higher and lower planetary systems. One should better take to the spiritual world to enjoy eternal life full of bliss and knowledge and never return to this miserable material existence. 

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