Shiva Purana
अवतारस्य विष्णोर्हि प्रजापालनहे तवे ॥ धर्मसंरक्षणार्थाय दुष्टानां दंडहेतवे ॥ २०॥
He was indeed an incarnation of Viṣṇu, for protecting the subjects, for the maintenance of virtue and for punishing the wicked.
english translation
avatArasya viSNorhi prajApAlanahe tave ॥ dharmasaMrakSaNArthAya duSTAnAM daMDahetave ॥ 20॥
hk transliteration by Sanscript