Karotosutta 1.6

1.6

Uttarañcepi gaṅgāya tīraṃ gaccheyya; dadanto dāpento yajanto yajāpento, natthi tatonidānaṃ puññaṃ, natthi puññassa āgamo.

If you were to go along the north bank of the Ganges giving and sacrificing and encouraging others to do the same, no merit comes of that, and no outcome of merit.