एतद्ध्येवाक्षरं ब्रह्म एतद्ध्येवाक्षरं परम् । एतद्ध्येवाक्षरं ज्ञात्वा यो यदिच्छति तस्य तत् ॥

ॐ

English Translation

This syllable Om is indeed Brahman. This syllable is the Highest. Whosoever knows this syllable obtains all that he desires. 

ॐ

English Commentary

Therefore, the word, indeed, is Brahman, (manifested). This word, indeed, is also the highest- Brahman. For, this word is the substitute for both of them. Whoso worships this word as Brahman obtains what he wants, i.e., the manifested or the unmanifested Brahman. If it be unmanifested, it should be known; if it be manifested, it should be reached.

Sri Shankaracharya