Mahabharata 12.242.20

आत्मनोऽव्ययिनो ज्ञात्वा इदं पुत्रानुशासनम्प्रयताय प्रवक्तव्यं हितायानुगताय च

ātmano'vyayino jñātvā idaṃ putrānuśāsanamprayatāya pravaktavyaṃ hitāyānugatāya ca

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