Taking as a bow the great weapon of the Upanishad, one should put upon it an arrow sharpened by meditation. Stretching it with a thought directed to the essence of That, penetrate that Imperishable as the mark, my friend.

Atharva Veda, Mundaka Upanishad 2.2.3. uph, 372

From all knowledge, yoga practice and meditation, all that relates to the Aum sound is to be meditated on as the only blissful (Siva). Indeed, the Aum sound is Siva.

Atharva Veda, Atharvasikha Upanishad 2. upb, 782

Contemplating Him who has neither beginning, middle, nor end-the One, the all-pervading, who is wisdom and bliss, the formless, the wonderful, whose consort is Uma, the highest Lord, the ruler, having three eyes and a blue throat, the peaceful-the silent sage reaches the source of Being, the universal witness, on the other shore of darkness.

Atharva Veda, Kaivalya Upanishad 7. ve, 764

There is no one greater in the three worlds than the guru. It is he who grants divine knowledge and should be worshiped with supreme devotion.

Atharva Veda, Yoga-Sikha Upanishad 5.53. yt, 26

Abiding in the midst of ignorance, but thinking themselves wise and learned, fools aimlessly go hither and thither, like blind led by the blind.

Atharva Veda, Mundaka Upanishad 1.2.8. upm, 77