Bhagavad Gita · Jnana Karma Sannyasa YogaChapter 4, Shloka 31 (4.31)

Two points — a result and a warning. (1) Partaking of what remains of the yajña → Brahman; (2) nāyaṃ loko 'sty ayajñasya — for one without yajña not even this world exists.

Shankaracharya: yathoktān yajñān kṛtvā tac-chiṣṭena kālena yathā-vidhi coditam annam amṛtākhyaṃ bhuñjate — having performed the yajñas described, in the remaining time they eat, according to rule, the food that is called nectar; mumukṣavaś cet kālātikramāpekṣayā — if they are seekers of liberation, they go (gradually, in the course of time) to the eternal Brahman. Na ayaṃ lokaḥ sarva-prāṇi-sādhāraṇo 'pi asti … ayajñasya — for one who has not even one of these yajñas, not even this world, common to all beings, exists — so where is another world, reached through special means?

Acharya Ramanuja: yajña-śiṣṭāmṛtena śarīra-dhāraṇaṃ kurvanta eva karma-yoge vyāpṛtāḥ — those engaged in karma-yoga, sustaining the body with the nectar that remains of the yajña, go to the eternal Brahman. Ayajñasya … na ayaṃ lokaḥ — for a person without the great yajñas and other daily duties, prākṛta-loka-sambandhi dharmārtha-kāmākhyaḥ puruṣārthaḥ na sidhyati — not even this world, that is, the human goals of dharma, artha and kama (righteousness, wealth, pleasure), is achieved — kutaḥ itaḥ anyaḥ mokṣākhyaḥ — so how could the other, called liberation, be?