Bhagavad Gita Chapter 14 Verse 9
भगवद् गीता अध्याय 14 श्लोक 9

सत्त्वं सुखे सञ्जयति रजः कर्मणि भारत।
ज्ञानमावृत्य तु तमः प्रमादे सञ्जयत्युत।।14.9।।



English Translation - Swami Gambirananda
14.9 O scion of the Bharata dynasty, sattva attaches one to happiness, rajas to action, while tamas, covering up knowledge, leads to inadvertence also.


English Translation of Ramanuja's Sanskrit Commentary
14.9 Sattva mainly attaches one to pleasure. Rajas mainly attaches one to actions. But Tamas, veiling knowledge of true things and being the cause of false knowledge, mainly attaches one to actions which are contrary to those which ought to be done.

The Sattva and other alities evolve from the nature of Prakrti, developed into the form of the body. Owing to this fact that they have evolved out of the nature of Prakrti, they always co-exist in bodies at all time. How, then, can they cause effects which are mutually contrary?  He replies:


Transliteration Bhagavad Gita 14.9Sattwam sukhe sanjayati rajah karmani bhaarata;
Jnaanamaavritya tu tamah pramaade sanjayatyuta.


Word Meanings Bhagavad Gita 14.9sattvam—mode of goodness; sukhe—to happiness; sañjayati—binds; rajaḥ—mode of passion; karmaṇi—toward actions; bhārata—Arjun, the son of Bharat; jñānam—wisdom; āvṛitya—clouds; tu—but; tamaḥ—mode of ignorance; pramāde—to delusion; sañjayati—binds; uta—indeed