Taittirīyopaniṣat 03.11

na kañcana vasatau pratyācakṣīta। tad vratam। tasmād yayā kayā ca vidhayā bahvannaṃ prāpnuyāt। arādhyasmā annamityācakṣate। etadvai mukhatonnagaṃ rāddham। mukhato'smā annagaṃ rādhyate। etadvai madhyato'nnagaṃ rāddham। madhyato'smā annagaṃ rādhyate। etadvā antatonnagaṃ rāddham। antato'smā annagaṃ rādhyate। ya evaṃ veda ॥11॥

Let him not refuse anyone who seeks to dwell (with him). That is the vow. Therefore, by whatever means one may obtain much food, people say: “Food should be served to him.” Indeed, this is success attained by serving the mouth with regard to food; through (serving) the mouth, he succeeds in attaining the food. Indeed, for him who knows thus: middle is the success attained regarding the food for one who is middle-aged; feet is the success attained regarding the food for one who is aged.

Taittirīya Bhāshya 03.11

Lord Vishnu, in the form of fire, water, earth, and ether, resides in food. He abides as both the enjoyer and the enjoyed, playing by himself. Mere enjoyability does not imply any inferiority in Him anywhere. Hence, never to disrespect the food, and never to say 'not welcome' to guests, are the two vows to be practiced.

"... vidyārthe vasatīcchayā। āgataṃ neti na brūyāt tadetad viduṣo vratam॥

"... For the sake of knowledge, when one comes with the desire to reside, one should not say 'not welcomed'; this is the vow of the wise.

sa viṣṇuḥ pṛthivī-nāmā pṛthutvāt prāṇa-nāmakaḥ। prakṛṣṭa-ānanda-balata ākāśaḥ sarva-vettr̥taḥ॥

He, Lord Viṣṇu, is known as 'Earth' because of his vastness; as 'Prāṇa', by virtue of supreme bliss and strength; as 'ether', by knowing all, as he is the knower of everything.

śarākhyadehinaś caiva śarīraṃ preraṇāt smṛtaḥ। etaiś caturbhir bhagavān rūpaiś ca caturātmabhiḥ॥

He is known as 'Śara', among the embodied, and is known through the impulse. By these four, the Lord manifests through forms and the fourfold selves.

bhogyabhoktṛsvarūpeṇa tiṣṭhati krīḍayā svayam। na ca bhogyatvamātreṇa hīnatvaṃ tasya kutracit॥

He abides as both the enjoyer and the enjoyed, playing by himself. Mere enjoyability does not imply any inferiority in him anywhere.

na hi bhāryopabhogyas tu bhartā hīnatvam āpnuyāt। evaṃ sa bhagavān viṣṇur aviśeṣo'khileṣv api॥

A husband is not to be treated as an object of enjoyment by the wife, for otherwise he would become inferior. In the same way, Lord Viṣṇu remains undifferentiated in all beings.

rūpeṣu krīḍate nityaṃ bhoktā bhogya itīcchayā। annākhyaṃ taṃ naiva nindyāt bahu manyeta taṃ sadā॥

He always plays among forms, being both the enjoyer and the enjoyed by desire; one should never blame him who is called food, but should always greatly respect him.

iti vratadvayaṃ hy etad bhāvyaṃ yadi sukhe spṛhā। yena kenāpi vidhinā bahvityeva janārdanam॥

Thus, if one desires happiness, these two vows must indeed be observed; by whatever means or method, as much as possible, and one should worship Lord Janardana (Krishna).

matvaiva prāpnuyānnityaṃ manovākkāyavṛttibhiḥ। ya evaṃ samupāsīta tasyānnākhyo hariḥ svayam॥

Having known thus, one should always attain (him) by the activities of mind, speech, and body. He who thus worships, for him Hari himself is called Anna (food).

siddha ityeva hi prāhurvidvāṃsaḥ pariniṣṭhitāḥ। yasya tad brahma saṃsiddhaṃ pūrvaṃ tenā'pyate'grataḥ॥

The wise who are well-established indeed say 'accomplished'; for one whose Brahman is perfectly attained before, by him it is obtained further on.

madhye vayasi cet siddhaṃ mukto madhyaṃ prapaśyati। vārdhake ced vijānāti muktaḥ pādau prapaśyati॥

If one attains realization in the middle of life, the liberated perceive the centre. If one realizes in old age, the liberated perceives the feet.

tejo-maṇḍalam eva anyat aṅgaṃ viṣṇoḥ prapaśyati। pūrve vayasi boddhavyam āmukhāt sarva-dṛṣṭaye॥"

In youth, one sees only the radiant circle as another limb of Viṣṇu. This should be understood from the outset for the complete vision."