Śrīmad-Bhāgavatam · Text 10.24.20
Who is speaking and story frame
वर्तेत ब्रह्मणा विप्रो राजन्यो रक्षया भुव: । वैश्यस्तु वार्तया जीवेच्छूद्रस्तु द्विजसेवया ॥ २० ॥
varteta brahmaṇā vipro
rājanyo rakṣayā bhuvaḥ
vaiśyas tu vārtayā jīvec
chūdras tu dvija-sevayā
The brāhmaṇa maintains his life by studying and teaching the Vedas, the member of the royal order by protecting the earth, the vaiśya by trade, and the śūdra by serving the higher, twice-born classes.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.