Bhagavad-Gita The Song Divine Chapter 18 (stanza 24-35)

That action, however, which involves much strain and is performed by one who seeks enjoyments or by a man full of egotism, has been spoken of as Rajasika. …. (24)

That action which is undertaken through sheer ignorance, without regard to consequences or loss to oneself, injury to others and one's own resourcefulness, is declared as Tamasika. …….. (25)

Free from attachment, un-egoistic, endowed with firmness and Zeal and un-swayed by success and failure - such a doer is said to be Sattvika. …………….. (26)

The doer, who is full of attachment, seeks the fruit of actions and is greedy, and who is oppressive by nature and of impure conduct, and who feels joy and sorrow, has been called Rajasika. ………………..  (27)

Lacking piety and self-control, un-cultured, arrogant, deceitful, and inclined to rob others of their livelihood, slothful, despondent and procrastinating - such a doer is called Tamasika. ……. (28)

Now here, Arjun, the threefold divine, based on the predominance of each Guna, of understanding (Buddhi) and firmness (Dhrti), which I shall explain in detail, one by one. …. (29)

The intellect which correctly determines the paths of activity and renunciation, what ought to be done and what should not be done, what is fear and what is fearlessness, and what is bondage and what is liberation,, that intellect is Sattvika. ………….. (30)

The intellect by which man does not truly perceive what is Dharma and what is Adharma, what ought to be done and what should not be done - that intellect is Rajasika. …… (31)

The intellect wrapped in ignorance, which imagines even Adharma to be Dharma, and sees all other things upside-down - that intellect is Tamasika, Arjun. ………… (32)

The unwavering perseverance by which man controls through the Yoga of meditation the functions of the mind, the vital airs and the senses - that firmness, Arjun, is Sattvika. …. (33)

The perseverance (Dhriti), however, by which the man seeking reward for his actions clutches with extreme fondness virtues, earthly possessions and worldly enjoyment - that perseverance (Dhriti) is said to be Rajasika, Arjun. ………….. (33)

The perseverance (Dhriti) by which an evil-minded person does not give up sleep, fear, anxiety, sorrow and vanity as well, that perseverance is Tamasika. ………. (35)