Chapter 1 · verse 43 · gita.yoga.org

Bhagavad Gita 1.43

दोषैरेतैः कुलघ्नानां वर्णसङ्करकारकैः। उत्साद्यन्ते जातिधर्माः कुलधर्माश्च शाश्वताः

By these evil deeds of the destroyers of the family, which cause confusion of castes, the eternal religious rites of the caste and the family are destroyed.