He who knowing this loudly pronounces (pranauti) that syllable, enters the same (imperishable) syllable, the Svara, the immortal, free from fear, and having entered it, becomes immortal, as the Devas are immortal.

In plain words: Anyone who understands this and chants Om enters that same deathless, fearless sound. Having entered it, that person becomes immortal, just like the gods.