मनुस्मृति - धर्म

नाऽधर्मश्चरितो लोके सद्यः फलति गौरिव ।
शनैरावर्तमानस्तु कर्तुर्मूलानि कृंतति ॥

- मनुस्मृति

The results of the deeds of cruelty (against dharma the code of life) are not immediately apparent unlike the benefits of domesticating a cow (you get milk on day one). Slowly the effects of mis-deeds surround the doer and cut the very roots of the source. Perpetrating cruelty will always end in the destruction of the culprit.

- Manu Smriti

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Update: Thanks Gayathri for pointing out the typo.