Those sinful persons who are ignorant of actual religious principles, yet consider themselves to be completely pious, without compunction commit violence against innocent animals who are fully trusting in them. In their next lives, such sinful persons will be eaten by the same creatures they have killed in this world.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
ये त्वनेवंविदोऽसन्तः स्तब्धाः सदभिमानिनः । पशून् द्रुह्यन्ति विश्रब्धाः प्रेत्य खादन्ति ते च तान्
ye tvanevaṃvido'santaḥ stabdhāḥ sadabhimāninaḥ | paśūn druhyanti viśrabdhāḥ pretya khādanti te ca tān
SB 11.5.14