By means of the hymns, one attains this world, by the sacrificial formulas, the space in-between, by holy chant, the world revealed by the sages. With the syllable Aum as his sole support, the wise man attains that which is peaceful, unaging, deathless, fearless—the Supreme. §
Atharva Veda, Praśna Upanishad 5.7. VE, 775§