Chapter 17 - Verse 13

विधिहीनमसृष्टान्नं मन्त्रहीनमदक्षिणम् ।
श्रद्धाविरहितं यज्ञं तामसं परिचक्षते ॥ १३ ॥

vidhihīnamasṛṣṭānnaṃ mantrahīnamadakṣiṇam .
śraddhāvirahitaṃ yajñaṃ tāmasaṃ paricakṣate .. 13 ..


They declare that worship to be Tamasic which is contrary to the ordinances, in which no food is distributed, which is devoid of mantras and gifts, and which is devoid of faith.
Read the commentary

Distributed : to brahmanas. Devoid of mantras : with hymns defective in utterance and accent. Gifts : prescribed fees (to priests).

Physical Austerity.

Now the three kinds of austerity will be described :