Kaṭhopaniṣad 2.15-16—ĀŪṀ: A Love Supreme

“I tell you briefly of that goal which all the Vedas propound with one voice, which all the austerities speak of, and wishing for which, people practise brahmācārya. It is this: ĀŪṀ. This letter ĀŪṀ, indeed, is the inferior Brahman Hiraṇyagarbha; and this letter is, indeed, the Supreme Brahman. Anybody, who, while meditating on this letter, wants any of the two, to him comes that.“