Shloka 13

परं हि ब्रह्म कथितं योगयुक्तेन तन्‍्मया । इतिहासं तु वक्ष्यामि तस्मिन्नर्थे पुरातनम्‌,उस समय योगयुक्त होकर मैंने परमात्मतत्त्वका वर्णन किया था। अब उस विषयका ज्ञान करानेके लिये मैं एक प्राचीन इतिहासका वर्णन करता हूँ

paraṁ hi brahma kathitaṁ yogayuktena tanmayā | itihāsaṁ tu vakṣyāmi tasminn arthe purātanam ||

“Indeed, the Supreme Brahman was described by me while I was absorbed in yoga. Now, in order to convey understanding of that very truth, I shall recount an ancient historical account connected with that subject.”

{'paraṁ''supreme, highest', 'hi': 'indeed, surely (emphatic particle)', 'brahma': 'Brahman
{'paraṁ':
the Absolute Reality', 'kathitam''was spoken, was explained', 'yoga-yuktena': 'by one united with yoga
the Absolute Reality', 'kathitam':
by one in disciplined spiritual absorption', 'tan-mayā''by me
by one in disciplined spiritual absorption', 'tan-mayā':
(also suggests) by me who was absorbed in That (tad-bhāva)', 'itihāsam''traditional history
(also suggests) by me who was absorbed in That (tad-bhāva)', 'itihāsam':
an instructive ancient narrative', 'tu''but/now (transition marker)', 'vakṣyāmi': 'I shall speak, I will tell', 'tasmin arthe': 'in/with regard to that meaning or topic', 'purātanam': 'ancient, of old'}
an instructive ancient narrative', 'tu':

वायुदेव उवाच

वायुदेव (Vāyudeva)
ब्रह्म (Brahman)
योग (Yoga)
इतिहास (Itihāsa)

Educational Q&A

The verse frames spiritual instruction: realization of the Supreme Brahman is best communicated not only through direct doctrine but also through an ancient itihāsa (exemplary narrative) that makes the same truth intelligible and ethically grounded.

Vāyudeva transitions from having previously taught the highest metaphysical truth in a yogic state to announcing that he will now narrate an ancient story relevant to that teaching, using narrative as a vehicle for conveying the same meaning.