Mahabharata 12.230.13

परिनिष्ठितकार्यो हि स्वाध्यायेन द्विजो भवेत्कुर्यादन्यन्न वा कुर्यान्मैत्रो ब्राह्मण उच्यते

pariniṣṭhitakāryo hi svādhyāyena dvijo bhavetkuryādanyanna vā kuryānmaitro brāhmaṇa ucyate

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