Dos and Don’t for the Brahmins according to DharmaShastras
The Gautama Dharmasutra states in verse 10.3 that it is obligatory on a Brahmin to learn and teach the Vedas. Chapter 10 of the text, according to Olivelle translation, states that he may impart Vedic instructions to a teacher, relative, friend, elder, anyone who offers exchange of knowledge he wants, or anyone who pays for such education. The Chapter 10 adds that a Brahmin may also engage in agriculture, trade, lend money on interest, while Chapter 7 states that a Brahmin may engage in the occupation of a warrior in the times of adversity. Typically, asserts Gautama Dharmasutra, a Brahmin should accept any occupation to sustain himself but avoid the occupations of a Shudra, but if his life is at stake a Brahmin may sustain himself by accepting occupations of a Shudra. The text forbids a Brahmin from engaging in the trade of animals for slaughter, meat, medicines and milk products even in the times of adversity.
The Apastamba Dharmasutra asserts in verse 1.20.10 that trade is generally not sanctioned for Brahmins, but in the times of adversity he may do so. The chapter 1.20 of Apastamba, states Olivelle, forbids the trade of the following under any circumstances: human beings, meat, skins, weapons, barren cows, sesame seeds, pepper, and merits.
The 1st millennium CE Dharmasastras, that followed the Dharmasutras contain similar recommendations on occupations for a Brahmin, both in prosperous or normal times, and in the times of adversity. The widely studied Manusmriti, for example, states:
Except during a time of adversity, a Brahmin ought to sustain himself by following a livelihood that causes little or no harm to creatures. He should gather wealth just sufficient for his subsistence through irreproachable activities that are specific to him, without fatiguing his body. – 4.2–4.3
He must never follow a worldly occupation for the sake of livelihood, but subsist by means of a pure, upright and honest livelihood proper to a Brahmin. One who seeks happiness should become supremely content and self controlled, for happiness is rooted in contentment and its opposite is the root of unhappiness. – 4.11–4.12
— Manusmriti, Translated by Patrick Olivelle
The Manusmriti recommends that a Brahmin’s occupation must never involve forbidden activities such as producing or trading poison, weapons, meat, trapping birds and others. It also lists six occupations that it deems proper for a Brahmin: teaching, studying, offering yajna, officiating at yajna, giving gifts and accepting gifts.] Of these, states Manusmriti, three which provide a Brahmin with a livelihood are teaching, officiating at yajna, and accepting gifts. The text states that teaching is best, and ranks the accepting of gifts as the lowest of the six. In the times of adversity, Manusmriti recommends that a Brahmin may live by engaging in the occupations of the warrior class, or agriculture or cattle herding or trade.[34] Of these, Manusmriti in verses 10.83–10.84 recommends a Brahmin should avoid agriculture if possible because, according to Olivelle translation, agriculture “involves injury to living beings and dependence of others” when the plow digs the ground and injures the creatures that live in the soil. However, adds Manusmriti, even in the times of adversity, a Brahmin must never trade or produce poison, weapons, meat, soma,