Pitṛgaṇa-Vibhāga (Classification of the Pitṛs) and the Śrāddha–Soma Nourishment Cycle
पितॄंस्ते ऽपूजयन्सर्वे नित्यमेव फलार्थिनः / एवमेते महात्मानः श्राद्धे सत्कृत्य पूजिताः
pitṝṃste 'pūjayansarve nityameva phalārthinaḥ / evamete mahātmānaḥ śrāddhe satkṛtya pūjitāḥ
Seeking the fruit of merit, they all continually worshipped the Pitṛs; thus, in the śrāddha rite, those great souls are honored and duly revered.