Gita Chapter 18.46 to 18.50

Yatah pravrittirbhootaanaam yena sarvamidam tatam;
Swakarmanaa tamabhyarchya siddhim vindati maanavah.
46. He from whom all the beings have evolved and by whom all this is pervaded, worshipping Him with his own duty, man attains perfection.
COMMENTARY: Man attains perfection by worshipping the Lord through the performance of his own duty, that is, he becomes qualified for the dawn of Self-knowledge.

Shreyaanswadharmo vigunah paradharmaat swanushthitaat;
Swabhaavaniyatam karma kurvannaapnoti kilbisham.
47. Better is one’s own duty (though) destitute of merits, than the duty of another well performed. He who does the duty ordained by his own nature incurs no sin.

Sahajam karma kaunteya sadoshamapi na tyajet;
Sarvaarambhaa hi doshena dhoomenaagnirivaavritaah.
48. One should not abandon, O Arjuna, the duty to which one is born, though faulty; for, all undertakings are enveloped by evil, as fire by smoke!

Asaktabuddhih sarvatra jitaatmaa vigatasprihah;
Naishkarmyasiddhim paramaam sannyaasenaadhigacchati.
49. He whose intellect is unattached everywhere, who has subdued his self, from whom desire has fled,—he by renunciation attains the supreme state of freedom from action.

Siddhim praapto yathaa brahma tathaapnoti nibodha me;
Samaasenaiva kaunteya nishthaa jnaanasya yaa paraa.
50. Learn from Me in brief, O Arjuna, how he who has attained perfection reaches Brahman, that supreme state of knowledge.

Gita Chapter 18.41 to 18.45

Braahmanakshatriyavishaam shoodraanaam cha parantapa;
Karmaani pravibhaktaani swabhaavaprabhavairgunaih.
41. Of Brahmanas, Kshatriyas and Vaishyas, as also the Sudras, O Arjuna, the duties are distributed according to the qualities born of their own nature!

Shamo damastapah shaucham kshaantiraarjavameva cha;
Jnaanam vijnaanam aastikyam brahmakarma swabhaavajam.
42. 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.

Shauryam tejo dhritirdaakshyam yuddhe chaapyapalaayanam;
Daanameeshwarabhaavashcha kshaatram karmaswabhaavajam.
43. Prowess, splendour, firmness, dexterity and also not fleeing from battle, generosity and lordliness are the duties of Kshatriyas, born of (their own) nature.

Krishigaurakshyavaanijyam vaishyakarma swabhaavajam;
Paricharyaatmakam karma shoodrasyaapi swabhaavajam.
44. Agriculture, cattle-rearing and trade are the duties of the Vaishya (merchant class), born of (their own) nature; and action consisting of service is the duty of the Sudra (servant class), born of (their own) nature.
COMMENTARY: When a man does his duties rightly according to his order of life, his heart gets purified and he goes to heaven.

Swe swe karmanyabhiratah samsiddhim labhate narah;
Swakarmaniratah siddhim yathaa vindati tacchrinu.
45. Each man, devoted to his own duty, attains perfection. How he attains perfection while being engaged in his own duty, hear now.

Gita Chapter 18.36 to 18.40

Sukham twidaaneem trividham shrinu me bharatarshabha;
Abhyaasaadramate yatra duhkhaantam cha nigacchati.
36. Now hear from Me, O Arjuna, of the threefold pleasure, in which one rejoices by practice and surely comes to the end of pain!

Yattadagre vishamiva parinaame’mritopamam;
Tatsukham saattwikam proktam aatmabuddhiprasaadajam.
37. That which is like poison at first but in the end like nectar—that pleasure is declared to be Sattwic, born of the purity of one’s own mind due to Self-realisation.

Vishayendriya samyogaad yattadagre’mritopamam;
Parinaame vishamiva tatsukham raajasam smritam.
38. That pleasure which arises from the contact of the sense-organs with the objects, which is at first like nectar and in the end like poison—that is declared to be Rajasic.

Yadagre chaanubandhe cha sukham mohanamaatmanah;
Nidraalasyapramaadottham tattaamasamudaahritam.
39. That pleasure which at first and in the sequel is delusive of the self, arising from sleep, indolence and heedlessness—such a pleasure is declared to be Tamasic.

Na tadasti prithivyaam vaa divi deveshu vaa punah;
Sattwam prakritijairmuktam yadebhih syaat tribhirgunaih.
40. There is no being on earth or again in heaven among the gods that is liberated from the three qualities born of Nature.