मनुस्मृति - मनःपूतं समाचरेत्

दृष्टिपूतं न्यसेत्पादं पस्त्रपूतं जलं पिबेत् ।
सत्यपूतां वदेद्वाचं मनःपूतं समाचरेत् ॥

- मनुस्मृति

One must set foot only after seeing (cleared after an inspection by the eye). One must drink water only after passing through a cloth. One must utter words that pass through the truth filter. One's actions must pass the conscience test.

- Manu Smriti