BG 17.26
सद्भावे साधुभावे च सदित्येतत्प्रयुज्यते
प्रशस्ते कर्मणि तथा सच्छब्दः पार्थ युज्यते
sadbhāve sādhubhāve ca sadityetatprayujyate
praśaste karmaṇi tathā sacchabdaḥ pārtha yujyate
TRANSLATION
This term Sat is used in the sense of existence and goodness. And so also, O Arjuna, the word Sat is applied to an auspicious action.
PURPORT
The word Sat is applied in Vedic and common usage, in respect of all contexts to express existence (Sadbhava) and auspiciousness (Sadhubhava). Similarly, in relation to any praiseworthy worldly act, viz., auspicious undertaking by someone, the word Sat is applied to express, ‘This is a good act.’