Taittiriya Upanishad 3.9.1

3.9.1

annaṃ bahu kurvīta /
tadavratam /
pṛthivī vā annam /
ākāśo 'nnādaḥ /
pṛthivyāmākāśaḥ pratiṣṭhitaḥ /
ākāśe pṛthivī pratiṣṭhitā /
tadetadannamanne pratiṣṭhitam /
sa ya etadannamanne pratiṣṭhitaṃ veda pratitiṣṭhati /
annavānannādo bhavati /
mahānbhavati prajayā
paśubhirbrahmavarcasena /
mahānkīrtyā // 1//
iti navamo 'nuvākaḥ //

His vow is that he should make food plentiful. Earth is food; space is the eater; for earth is placed in space. (Space is food; and earth is eater, for) space is placed on earth. Thus one food is lodged in another food. He who knows thus that one food is lodged in another, gets firmly established. He becomes a possessor and an eater of food. He becomes great in progeny, cattle, and the lustre of holiness and great in glory.