बुद्धेर्भेदं धृतेश्चैव गुणतस्त्रिविधं श्रृणु।प्रोच्यमानमशेषेण पृथक्त्वेन धनञ्जय ॥

Teachers usually read this idea across several verses together, one shared reflection covers the whole unit.

• 18.29Hear thou the threefold division of intellect and firmness, according to the Gunas, as I declare them fully and distinctly, O Arjuna.

• 18.30The intellect which knows the path of work and renunciation, what should be done and what should not be done, fear and fearlessness, bondage and liberation—that intellect is Sattvic (pure), O Arjuna.
• 18.31That by which one wrongly understands dharma and adharma, and also what ought to be done and what ought not to be done—that intellect, O Arjuna, is rajasic (passionate).
• 18.32That intellect, O Arjuna, which is enveloped in darkness and sees Adharma as Dharma and all things perverted, is Tamasic (dark).
• 18.33The unwavering firmness, through which Yoga restrains the functions of the mind, life-force, and senses—that firmness, O Arjuna, is Sattvic (pure).
• 18.34But that, O Arjuna, by which one holds fast to Dharma (duty), enjoyment of pleasures, and earning of wealth, on account of attachment and desire for reward—that firmness, O Arjuna, is Rajasic (passionate).
• 18.35That firmness, O Arjuna, by which a stupid man does not abandon sleep, fear, grief, despair, and conceit, is Tamasic.
• 18.36And now, O Arjuna, hear from Me of the threefold pleasure, in which one rejoices through practice and surely comes to the end of pain.
• 18.37That which is like poison at first but in the end like nectar—that happiness is declared to be sattvic, born of the purity of one's own mind due to self-realization.
• 18.38That happiness which arises from the contact of the senses with the objects, which is initially like nectar but eventually like poison, is said to be Rajasic.
• 18.39That happiness which at first, as well as in the end, deludes the self, and which arises from sleep, indolence, and heedlessness—that is declared to be Tamasic.
• 18.40There is no being on earth or in heaven among the gods that is liberated from the three qualities born of Nature.

cha

and

eva

certainly

bhedam

the distinctions

buddheḥ

of intellect

dhanañjaya

conqueror of wealth, Arjun

dhṛiteḥ

of determination

śhṛiṇu

hear

prochyamānam

described

aśheṣheṇa

in detail

pṛithaktvena

distinctly

guṇataḥ tri-vidham

according to the three modes of material nature