Vishnupurana 3.18.p7

3.18.p7

He who eats himself without satisfying the gods, manes, spirits and guests feeds upon his own iniquity and there is no salvation for such a person. The Brāhmans are men of other castes who neglect their respective duties or take up a degraded profession are said to be naked. To live in a place where there is an intermixture of four castes is detrimental to the character of the righteous. Those who converse with him who eats without offering a portion to the gods, the sages, the manes, spirits and guests, are doomed to hell. A wise man should not therefore talk with or come in contact with these heretics who are rendered impure for renouncing the three Vedas. A Srāddha ceremony, although performed with great care and devotion, if looked upon by these heretics does not please the gods or progenitors.