स एष रसानांरसतमः परमः परार्ध्योऽष्टमो यदुद्गीथः ॥ १.१.३ ॥
sa eṣa rasānāṃrasatamaḥ paramaḥ parārdhyo’ṣṭamo yadudgīthaḥ || 1.1.3 ||
3. This udgītha [Om] is the best of all essences. It is the best of all that exists. It is the eighth, and it has the highest status.
Saḥ, that; eṣaḥ, this; rasānām, of all the essences; rasatamaḥ, the best essence; paramaḥ, the best; parārdhyaḥ, ranking the highest; aṣṭamaḥ, the eighth [in the order of earth, water, plants, human beings; speech, the Ṛg Veda, the Sāma Veda, and udgītha]; yāt, that; udgīthaḥ, udgītha [Om].
The best of all essences is the udgītha, which is Om. It is the highest and best because it is the same as Brahman.