Mahabharata 14.45.22

त्रीणि कर्माणि यानीह ब्राह्मणानां तु जीविकायाजनाध्यापने चोभे शुद्धाच्चापि प्रतिग्रहः

trīṇi karmāṇi yānīha brāhmaṇānāṃ tu jīvikāyājanādhyāpane cobhe śuddhāccāpi pratigrahaḥ

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