divi surya-sahasrasya
bhaved yugapad utthita
yadi bhah sadrsi sa syad
bhasas tasya mahatmanah
diviin the sky; surya—sun; sahasrasyaof many thousands; bhavetthere were; yugapatsimultaneously; utthitapresent; yadiif; bhahlight; sadrsilike that; sa—that; syatmay be; bhasaheffulgence; tasyathere is; mahatmanahof the great Lord.
If hundreds of thousands of suns rose up at once into the sky, they might resemble the effulgence of the Supreme Person in that universal form.
What Arjuna saw was indescribable, yet Sanjaya is trying to give a mental picture of that great revelation to Dhrtarastra. Neither Sanjaya nor Dhrtarastra were present, but Sanjaya, by the grace of Vyasa, could see whatever happened. Thus he now compares the situation, as far as it can be understood, to an imaginable phenomenon (i.e. thousands of suns).

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