Mahabharata 1.1.28

युगस्यादौ निमित्तं तन्महद्दिव्यं प्रचक्षतेयस्मिंस्तच्छ्रूयते सत्यं ज्योतिर्ब्रह्म सनातनम्

yugasyādau nimittaṃ tanmahaddivyaṃ pracakṣateyasmiṃstacchrūyate satyaṃ jyotirbrahma sanātanam

Our plain-language meaning of this verse is waiting for scholar review.