Shiva Purana
तस्माद्दुःखात्मिकां हिंसां कुर्वाणो यः सनिर्घृणः ॥ इति निर्बंधयंत्येके नियमो नेति चापरे ॥ ३७ ॥
Hence we shall say that he who inflicts injury ultimately painful is ruthless. Thus a few insist upon this condition. Others do not.
english translation
tasmAdduHkhAtmikAM hiMsAM kurvANo yaH sanirghRNaH ॥ iti nirbaMdhayaMtyeke niyamo neti cApare ॥ 37 ॥
hk transliteration by Sanscript