Verse
अश्रद्धया हुतं दत्तं तपस्तप्तं कृतं च यत् ।असदित्युच्यते पार्थ न च तत्प्रेत्य नो इह ॥
aśraddhayā hutaṃ dattaṃ tapastaptaṃ kṛtaṃ ca yatasadityucyate pārtha na ca tatpretya no iha
Whatever is wrought without faith, oblation, giving, askesis or other work, Asat it is called, O Partha; it is nought, here or hereafter.
Gītā 17·28