Bhagavatapurana 4.13.32

4.13.32

tathā sādhaya bhadraṃ te ātmānaṃ suprajaṃ nṛpa /
iṣṭas te putra-kāmasya putraṃ dāsyati yajña-bhuk //

32. "Good betide thee! do thou so endeavour in securing an issue to thyself that the gods may be pleased to accept thy offerings; when properly worshipped the Yajna Purusha (the god of fire) will bless thee with an issue which thou seekest.