SB 4.9.22

TEXT 22
 
TEXT
प्रस्थिते तु वनं पित्रा दत्त्वा गां धर्मसंश्रयः ।
षट्त्रिंशद्वर्षसाहस्रं रक्षिताव्याहतेन्द्रियः ॥ २२ ॥
prasthite tu vanam pitra
dattva gam dharma-samsrayaḥ
sat-trimsad-varsa-sahasram
raksitavyahatendriyaḥ
prasthite-after departure; tu-but; vanam-to the forest; pitra-by your father; dattva-awarding; gam-the whole world; dharma-samsrayaḥ-under the protection of piety; sat-trimsat-thirty-six; varsa-years; sahasram-one thousand; raksita-you will rule; avyahata-without decay; indriyaḥ-the power of the senses.
TRANSLATION
After your father goes to the forest and awards you the rule of his kingdom, you will rule the entire world continuously for 36,000 years, and all your senses will continue to be as strong as they are now. You will never become old.
PURPORT
In the Satya-yuga people generally lived for 100,000 years. Dhruva Maharaja's ruling the world for 36,000 years was quite possible in those days.

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