Whatever there is-the whole universe-vibrates because it has gone forth from Brahman, which exists as its Ground. That Brahman is a great terror, like a poised thunderbolt. Those who know It become immortal.
Yajur Veda, Katha Upanishad, Part Two, Chapter III, 2
If a man is able to realise Brahman here, before the falling asunder of his body, then he is liberated; if not, he is embodied again in the created worlds.
Yajur Veda, Katha Upanishad, Part Two, Chapter III, 4
As in a mirror, so in the buddhi; as in a dream, so in the World of the Fathers; as in water, so Brahman is seen in the World of the Gandharvas; as in light and shade, so in the World of Brahma.
Yajur Veda, Katha Upanishad, Part Two, Chapter III, 5
The one who knows you thus, O Breath, and that which forms your support, to him will all offer tribute in yonder highest heaven.
Atharva Veda XI, 4, 18
Just as all creatures owe tribute to you, Breath of Life, so may they bring it to the one who hears you, O renowned!
Atharva Veda XI, 4, 19