Bhagavan Krishna in chapter Eighteen, Verse 40 says that there is no being on earth or in heaven among the gods that is liberated from the three qualities of nature (gunas).  The four varnas – Brahmana, kshatriya, Vaisya and Sudra, their duties are distributed according to their gunas.

Serenity, self-restraint, austerity, purity, forgiveness and also uprightness, knowledge, realisation and belief in God are the duties of the Brahmanas born of their own nature (dominating sattva guna).

Prowess, splendour, firmness, natural instinct to fight in battle, generosity, and lordliness are the duties of the kshatriyas born of their own nature (dominating rajo guna).

Agriculture, cattle-rearing, trade are the duties of the vaisya (merchant class) born of their own nature (dominating rajas and tamas).

Doing service to all the other varnas is the nature of the sudra (dominating tamo guna).

When a person performs his duty according to his varna then he attains perfection through karma.

Doing one’s own duty with enthusiasm, devotion and perfection to one’s own knowledge is considered as the worship to the Supreme. There is no discrimination of any duty. Duty is a duty.  Whether it is profitable, high earning, status – all these differences are for man; and not for God.  Work is worship.

He from whom all the being has evolved and by whom all this are pervaded – worshipping Him with one’s own duty, man attains perfection.  One should select the duty according to his nature. One should not select a duty (work) due to financial or material benefits.  Then we cannot do the duty with interest and passion for the work; we would rather do it for benefits. In such case, it will not lead one to reach the higher goals in life.  He who does the duty ordained by his own nature incurs no sin.  One should not abandon one’s own duty, then it will incur sin.

Till when, is one ordained to do his own duty?

Till one identifies with his own Self, one has to do their own duty.  Now we identify with our body and mind. By performing our duty with perfection and devotion one attains purity of the mind and this enables one to attain knowledge. By knowledge one identifies with the Self. Till then one has to perform their own duty born of their inherent nature

Now, Bhagavan Krishna explain about how the duty makes one perfect and how he behaves.

One endowed with pure intellect, controlling the senses and the mind, abandoning attraction and hatred, interested in dwelling in solitude, eating little, with speech, body and mind subdued, always engaged in meditation, resorting to dispassion, having abandoned egoism, arrogance, desire, anger and covetousness and he always remain peaceful. Such a person is fit to attain Brahman.

Becoming Brahman, serene in the Self, he neither grieves nor desires, he is the same to all beings, he obtains supreme devotion to God. Bhagavan says that, by devotion he knows Me in truth, what and who I am, then having known Me in truth, he enters into the Me, the Supreme.

Now Bhagavan concludes His discourse with some beautiful words.

Mentally renounce all actions in Me, having Me as the highest Goal, always fix your mind on Me.  By My grace you Shall overcome all obstacles.  One’s own nature will not allow one to sit idle.  Bhagavan says that, I dwell in the hearts of all beings and I am the cause of all beings, by My illusive power, I revolve all as if mounted on a machine. Fix your mind on Me, be devoted to Me, Sacrifice to Me, bow down to Me, you shall come to Me, truly do I promise to you. Bhagavan Krishna says that, abandoning all duties take refuge in Me alone, I will liberate you from all sins, MA SHUCHA: Do not grieve.

Bhagavan says that one who hear, read, teach this dialogue between Myself and Arjuna will definitely reach Me.

Yatra yogeshwar: krishna:  Yatra partho dhanur dhara:

Tatra srirvijayo bhuti druvo nithir mathirmama.

Wherever is Krishna, the Lord of yoga, wherever is Arjuna, the wielder of the bow; there is prosperity, victory, happiness and firmness; such is my conviction says, Sanjaya and concludes retelling Gita to king Dhritarashtra.