In the 19th chapter, the Lord tells Uddhava that the threefold manifestations starting with birth etc, that crops up in the jeevas as per their past karmas, is a product of Maya (prakriti) and is not the inherent character of the jeeva, which is one of eternal knowledge and bliss.
Modifications befall the jeeva at the beginning of creation; neither during pralaya (dissolution) nor in mukti (liberation). Uddhava then implores the Lord to expound the most sanctifying and ancient wisdom, coupled with dispassion and intuition as well as the path of devotion, through which mortals tormented on all sides by the threefold agonies and undergoing intense suffering in metempsychosis could redeem themselves. The Lord tells Uddhava that the very same question was asked by King Yudhistira, of Bhisma, at the end of the Mahabharata war and repeats the answer provided by Bhisma.
Understanding of all 28 categories viz; prakriti, purusha, mahat, ahankara, the 5 subtle elements, 5 senses of perception, 5 organs of actions, mind, 5 gross elements and the 3 gunas, present in all the jeevas and realizing that the Supreme Lord is the sole controller of all these tattvas-is Jnana. When, under the guidance of an all-knowing Guru, the Jnani goes deeper into the subtler aspects of such jnana, according to his capacity to intuit the same, such specialized jnana is called vijnana. The Supreme Lord is the only Sovereign Independent who is there at the beginning of creation, in the middle to sustain it and who remains at the end when all creation is dissolved. The path of devotion- Bhakti Yoga-is the royal road to emancipation. When the mind equipped with sattva and therefore tranquil, is devoted to the Lord, man automatically acquires piety, wisdom coupled with dispassion and divine powers.
When however the same mind is set on various objects, it wanders along with the senses and gets all the more stained with rajas and addicted to evil. Regulations such as being faithful to the Lord, non violence, truthfulness, controlling senses etc which engender devotion to the Lord, is termed as Dharma. Now Uddhava wants to know from the Lord, how many types and varieties of yama and niyama are there, what is meant by Sama, dama, titiksha, tyaga, satyam etc. A detailed reply by the Lord follows.
The Lord finally concludes” what is to be gained by elaborate discussion? The definition of good and evil (in a nutshell) is as follows: to direct ones eyes to the virtues and faults of others is evil, while virtue lies in developing a disposition entirely free from the habit of seeing the virtues and faults of others”. Thus ends the nineteenth chapter.