In plain words
When obligatory action is performed simply because it ought to be done, Arjuna, abandoning attachment and fruit, that Tyāga is regarded as sāttvika.
Word for word
Which obligatory action is done only as 'to be done', O Arjuna, having given up attachment and also the fruit, that tyāga is held sāttvika.
कार्यमित्येव यत् कर्म नियतं क्रियतेऽर्जुनसङ्गं त्यक्त्वा फलं चैव स त्यागः सात्त्विको मतः
Other commentaries
The commentators
▸Bhagavadgītābhāṣyam
कः पुनः सात्त्विकः त्यागः इति, आह —
कार्यं कर्तव्यम् इत्येव यत् कर्म नियतं नित्यं क्रियते निर्वर्त्यते हे अर्जुन, सङ्गं त्यक्त्वा फलं च एव । एतत् नित्यानां कर्मणां फलवत्त्वे भगवद्वचनं प्रमाणम् अवोचाम । अथवा, यद्यपि फलं न श्रूयते नित्यस्य कर्मणः, तथापि नित्यं कर्म कृतम् आत्मसंस्कारं प्रत्यवायपरिहारं वा फलं करोति आत्मनः इति कल्पयत्येव अज्ञः । तत्र तामपि कल्पनां निवारयति ‘फलं त्यक्त्वा’ इत्यनेन । अतः साधु उक्तम् ‘सङ्गं त्यक्त्वा फलं च’ इति । सः त्यागः नित्यकर्मसु सङ्गफलपरित्यागः सात्त्विकः सत्त्वनिर्वृत्तः मतः अभिप्रेतः ॥
ननु कर्मपरित्यागः त्रिविधः संन्यासः इति च प्रकृतः । तत्र तामसो राजसश्च उक्तः त्यागः । कथम् इह सङ्गफलत्यागः तृतीयत्वेन उच्यते ? यथा त्रयो ब्राह्मणाः आगताः, तत्र षडङ्गविदौ द्वौ, क्षत्रियः तृतीयः इति तद्वत् । नैष दोषः त्यागसामान्येन स्तुत्यर्थत्वात् । अस्ति हि कर्मसंन्यासस्य फलाभिसन्धित्यागस्य च त्यागत्वसामान्यम् । तत्र राजसतामसत्वेन कर्मत्यागनिन्दया कर्मफलाभिसन्धित्यागः सात्त्विकत्वेन स्तूयते ‘स त्यागः सात्त्विको मतः’ इति ॥ ९ ॥
In plain words
"And which kind of tyāga is the sāttvika one?" To this, he says —
'It must be done, it is one's duty' — whatever obligatory, ever-recurring action gets performed, Arjuna, it must be done only after giving up both attachment and fruit. I have already cited this very verse as the Lord's own proof that obligatory rites do bear fruit. Or, put another way: even though scripture never explicitly names a fruit for obligatory action, an unenlightened person still ends up assuming one anyway — either that it refines the self, or that it simply wards off the demerit of neglect. The verse rules out even that assumption, with the words 'having given up fruit'. So it was exactly right to say 'having given up attachment and fruit'. That is what relinquishment means, applied to obligatory action — giving up attachment and fruit together — and that is precisely what is meant by calling it sāttvika, born of sattva.
One might object: we already established that the relinquishment of action, called renunciation, comes in three kinds, and that the tamasic and rajasic types of relinquishment have been named. So how can the relinquishment of attachment and fruit be introduced here as a third kind? It's a bit like three brahmins arriving, only to find that two are genuine scholars of the six Vedāṅgas, and the third turns out to be a kṣatriya — a strange kind of 'third' indeed. But there's no real flaw here — because all three share the common feature of being relinquishment, and because the grouping exists for the sake of praise, not exact parallel. There really is a shared genus linking the renunciation of action to the relinquishment of wanting fruit — both, after all, are forms of giving up. What happens is this: by censuring action-relinquishment in its rajasic and tamasic guises, the relinquishment of fruit-intent gets praised, by contrast, as the sāttvika one: 'that relinquishment is held to be sāttvika,' as the verse itself says.
Close to the Sanskrit
"But which relinquishment is sāttvika?" — thus; he says —
'Is to be done, is one's duty' — thus indeed; whatever action, obligatory, constant, is performed, carried out, O Arjuna — having abandoned attachment and fruit indeed. This we have already cited as authoritative proof, the Lord's own statement, regarding the fruitfulness of obligatory actions. Or alternatively: although no fruit is explicitly stated of obligatory action, nevertheless the ignorant one indeed imagines that obligatory action, once performed, produces for the self a fruit — either refinement of the self or the warding-off of the sin of omission. There, the verse dispels even that supposition too, by this: 'having abandoned fruit'. Therefore it was rightly said: 'having abandoned attachment and fruit'. That relinquishment, in obligatory actions — the relinquishment of attachment and fruit — is held, is intended, as sāttvika, arising from sattva.
Now, the relinquishment of action, threefold, called renunciation, was already established; there, tamasic and rajasic relinquishment have been declared. How then is the relinquishment of attachment and fruit spoken of here as a third? Just as three brahmins arrived — among them two were knowers of the six Vedāṅgas, and a kṣatriya was the third — so too here. This is not a flaw, because of a common feature of relinquishment, and because of having the purpose of praise. For there is indeed a commonality of being-relinquishment shared by the renunciation of action and the relinquishment of the intention for fruit. There, through the censure of action-relinquishment by virtue of being rajasic and tamasic, the relinquishment of the intention for the fruit of action is praised by virtue of being sāttvika: 'that relinquishment is held to be sāttvika', thus.