Next are the duties and disposition for a ksatriya, for whom rajas is predominant and sattva is secondary.
śauryaṁ tejo dhṛtirdākṣyaṁ yuddhe cāpyapalāyanam । dānamīśvarabhāvaśca kṣātraṁ karma svabhāvajam ॥18.43॥ Valour, self-confidence, resolve, adroitness, not running (away) from conflict, giving, and overlordship (leadership) are the naturally born duties and disposition of a ksatriya.
A person who has śauryaṁ is highly skilled and brave in warfare or any dangerous situation. tejo is the brilliance born of self-confidence, and dhṛti is sustained enthusiasm. He is a person who does not postpone, but does what is to be done at the right time and is even ready for a surprise. Some people can only operate when they have a plan and everything happens according to that plan. But this person has readiness to change, completely reshuffle the ideas, uses any resources to face the situations is called dākṣyaṁ.
Another duty or disposition of a ksatriya is not running away in a situation where he has to fight it out - yuddhe apalāyanam. dānam - giving is also very important. īśvarabhāva - overlordship which is ruling power evident to those who are to be governed. The duty of a ksatriya is definitely to govern, and if he is a ksatriya by guna, this is very natural to him. When rajas is predominant, and sattva is second, it would be his natural tendency to rule. Because he has sattva, he will not be self-centred, but will have a community ego or an ideological ego. He will be ready to sacrifice his family and his own comforts to fulfil that ideology. The problem is, he doesn’t see beyond the ideal, but thinks that it is everything. There is nobility in his thinking because of sattva, but it is not complete because of the presence of rajas.
kṛṣigaurakṣyavāṇijyaṁ vaiśyakarma svabhāvajam ।
paricaryātmakaṁ karma śūdrasyāpi svabhāvajam ॥ 18-44॥ Agriculture, tending cattle, and commerce are the natural duties of a vaiśya. The natural duty of a śudra is in the form of service.
kṛṣi is any activity connected to cultivation. gaurakṣya is protection of cow. This is not cow farming which means raising cattle for slaughter. The cattle are protected, based on the principle that what is protected protects you in turn. An agriculturalist requires the help of cattle, so their protection is part of his daily chores. Another duty of the vaiśya is commerce - vāṇijyaṁ. All traders, manufacturers, industrialists, etc., are engaged in vaiśya-karma. It is born of guna, and therefore, is natural - svabhāvajam.
Same as ksatriya whose rajas is predominant, however for vaiśya, tamas is second nature, not sattva. Naturally, he is going to be selfish, but if he converts his activities into duties, he can develop more sattva.
Then we have śūdra, in whom tamas is predominant and rajas is second. His activity consists of any type of service - paricarya. Every society has this group of people who provide the hands and legs behind all the different functions. But whatever the activity is, it has to be converted into a duty. That is the point here.
Śankarācārya says that those who perform well the duties enjoined for their varna naturally gain heaven as the result, and he quotes the following from the āpastamba smrti, “those who are committed to following their own duties according to varna and stage of life, experiencing the result after death, because of the remaining (punya), gain a birth that is better in term of place, varna, family, duty, longevity, learning, profession, wealth, happiness and intelligence.”