Mahabharata 12.59.87
युगानामायुषो ह्रासं विज्ञाय भगवाञ्शिवःसंचिक्षेप ततः शास्त्रं महार्थं ब्रह्मणा कृतम्
yugānāmāyuṣo hrāsaṃ vijñāya bhagavāñśivaḥsaṃcikṣepa tataḥ śāstraṃ mahārthaṃ brahmaṇā kṛtam
Our plain-language meaning of this verse is waiting for scholar review.
Open in the book