Manava Dharmashastra 5.35

5.35

sambhavān janmāni | avaśyaṃ prāptātyayasambhave devārcanaṃ yo na karoti atha ca māṃsamaśnāti sa duṣyatyeva |

But when invited according to law, if a man does not e at meat, he becomes, after death, a beast, during twenty- one births.—(35)

Medhātithi’s commentary (manubhāṣya):
‘Sambhava’ stands for janma, birth.

Except when there is danger to life through hunger, if a man does not worship the Gods, and yet eats meat, he certainly incurs sin.—(35)