Atharvavedaparishishta 26.2.6

26.2.6

[yad yatra lakṣaṇaṃ proktaṃ yasmin kāle yathāvidhi | tatra tenaiva siddhiḥ syād viparīte tathā bhayam] ||

[Whatever characteristic is taught for a particular [rite], at whatever time, according to rule: / by that alone success will occur there; if it is otherwise, there will be fear.]