eta bhāvi' kali-kāle prathama sandhyāya
avatīrṇa hailā kṛṣṇa āpani nadīyāya
eta—thus; bhāvi'-thinking; kali-kāle—in the Age of Kali; prathama—first; sandhyāya—in the junction; avatīrṇa hailā—descended; kṛṣṇa—Lord Kṛṣṇa; āpani—Himself; nadīyāya—in Nadia.
Thinking thus, the Personality of Godhead, Śrī Kṛṣṇa Himself, descended at Nadia early in the Age of Kali.
The prathama-sandhyā is the beginning of the age. According to astronomical calculation, the age is divided into twelve parts. The first of these twelve divisions is known as the prathama-sandhyā. The prathama-sandhyā and śeṣa-sandhyā, the last division of the preceding age, form the junction of the two ages. According to the Sūrya-siddhānta, the prathama-sandhyā of Kali-yuga lasts 36,000 solar years. Lord Caitanya appeared in the prathama-sandhyā after 4,586 solar years of Kali-yuga had passed.
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