A mighty weapon, the Upanishad. Take it as a bow. Affix an arrow sharpened by devotion. Bend the bow by a thought concentrated on That. Hit the target, my dear-the Imperishable. Aum is the bow, the atman is the arrow; Brahman, they say, is the target tobe pierced by concentration. Thus one become, united with Brahman as an arrow with the target.
Krishna Yajur Veda, Mahanarayana Upanishad 540-541. ve, 774
Having realized with mind and heart, having become wise, you will no longer move on the path of death. Therefore, they call renunciation the ardor surpassing all others.
Krishna Yajur Veda, Mahanarayana Upanishad 537-8. ve, 439
There, where there is no darkness, nor night, nor day, nor being, nor nonbeing, there is the Auspicious One, alone, absolute and eternal. There is the glorious splendor of that Light from whom in the beginning sprang ancient wisdom.
Krishna Yajur Veda, Svetasvatara Upanishad 4.18. ve, 83-84
By the power of inner harmony and by the grace of God, Svetasvatara had the vision of Brahman. He then spoke to his nearest hermit-students about the supreme purification, about Brahman, whom the seers adore.
Krishna Yajur Veda, Svetasvatara Upanishad 6.21. upm, 97
Homage to the source of health, and to the source of delight. Homage to the maker of health and to the maker of delight. Homage to the Auspicious and to the more Auspicious. (Namastaraya namah sambhave cha mayobhave cha, namah sankaraya cha mayaskaraya cha, namah sivaya cha sivataraya cha.)
Krishna Yajur Veda, Taittiraya Samhita 4.5.8. yvk, 35 (Namah Sivaya, at the center of the Vedas