Verse 4.11.1

अथ हैनं गार्हपत्योऽनुशशास पृथिव्यग्निरन्नमादित्य इति य एष आदित्ये पुरुषो दृश्यते सोऽहमस्मि स एवाहमस्मीति ॥ ४.११.१ ॥

atha hainaṃ gārhapatyo'nuśaśāsa pṛthivyagnirannamāditya iti ya eṣa āditye puruṣo dṛśyate so'hamasmi sa evāhamasmīti || 4.11.1 ||

1. Then the Gārhapatya fire said to him [Upakosala]: ‘The earth, fire, food, and the sun—these are all part of my [i.e., part of Brahman’s] body. The person seen in the solar orb is me. I am that’.

Word-for-word explanation:

Atha ha enam gārhapatyaḥ anuśaśāsa, next the Gārhapatya fire gave him this instruction; pṛthivī agniḥ annam ādityaḥ iti, the earth, fire, food, and the sun [are all part of me—i.e., of Brahman]; yaḥ eṣaḥ āditye puruṣaḥ dṛśyate, the person seen in the sun; saḥ aham asmi saḥ eva aham asmi iti, I am he, I am he.

Commentary:

First the fires taught Upakosala together. Now they are teaching him separately. The Gārhapatya fire begins.

He said: ‘The earth, fire, food, and the sun—these constitute my body. I divide myself into these things. There in the solar region is a person. That is me. I am known as the Gārhapatya fire and I am also this person in the solar region. Earth and food are both objects of enjoyment and consumption, but fire and the sun are not in this category. They are similar to each other, however, just as food and the earth are similar to each other, being objects that people can enjoy.’