Bhagavad Gita 17.27

अश्रद्धया हुतं दत्तं तपस्तप्तं कृतं च यत् |
असदित्युच्यते पार्थ न च तत्प्रेत्य नो इह

Translation

O son of Pritha, whatever acts of sacrifice, charity, or penance are done without faith, are termed as “Asat.” They are useless both in this world and the next.