The eighteenth chapter of the Bhagavad Gita is Moksha Sanyas Yoga. Arjuna requests the Lord to explain the difference between the two types of renunciations - sanyaas(renunciation of actions) and tyaag(renunciation of desires). Krishna explains that a sanyaasi is one who abandons family and society in order to practise spiritual discipline whereas a tyaagi is one who performs their duties without attachment to the rewards of their actions and dedicating them to the God. Krishna recommends the second kind of renunciation - tyaag. Krishna then gives a detailed analysis of the effects of the three modes of material nature. He declares that the highest path of spirituality is pure, unconditional loving service unto the Supreme Divine Personality, Krishna. If we always remember Him, keep chanting His name and dedicate all our actions unto Him, take refuge in Him and make Him our Supreme goal, then by His grace, we will surely overcome all obstacles and difficulties and be freed from this cycle of birth and death.
That action is said to be born of tamas which is undertaken out of delusion, (and) without consideration of its conscience, loss, harm and ability.OPEN VERSE
The agent who is free from attachment [Attachment to results or the idea of agentship.], not egotistic, endowed with fortitude and diligence, and unperturbed by success and failure is said to be possessed of sattva.OPEN VERSE
The agent who has attachment, who is desirous of the results of actions, covetous, cruel by nature, unclean and subject to joy and sorrow is declared to be possessed of rajas.OPEN VERSE
The agent who is unsteady, naive, unbending, deceitful, wicked, lazy, morose and procrastinating is said to be possessed of tamas.OPEN VERSE
O Dhananjaya, listen to the classification of the intellect as also of fortitude, which is threefold according to the gunas, while it is being stated elaborately and severally.OPEN VERSE