That which is neither internal consciousness nor external consciousness nor both together, which does not consist solely in compact consciousness, which is neither conscious nor unconscious, which is invisible, unapproachable, impalpable, indefinable, unthinkable, unnameable, whose very essence consists of the experience of its own self, which absorbs all diversity, is tranquil and benign, without a second, which is what they call the fourth state — that is the atman. This it is which should be known.
Atharva Veda, Mandukya Upanishad 2.7. VE, P. 723
Revealed and yet dwelling hidden in the cave is that which is called the great Abode. Whatever moves and breathes and blinks is fixed therein. Know this as being and also nonbeing, the desire of all hearts, transcending knowledge, best beloved of every creature. Burning as a flame and subtlest of the subtle, in which are firmly fixed the worlds and their peoples — that is the imperishable Brahman. That is life and word and spirit, the true, the immortal! That, my friend, is to be known — know that!
Atharva Veda, Mundaka Upanishad 2.2.1-2, VE, P. 685
Next follows the fulfilment of prayers. One should thus meditate on the object one wishes to obtain through meditation: he (i.e. the udgatri priest) should meditate on the Saman with which he is going chant the praise.
Sama Veda, Chandogya Upanishad I, III – Meditation on the Udgitha as the Sun and the Vyana, 8
He (the udgatri priest) should meditate on the Rik in which that Saman occurs, on the rishi to whom it was revealed and on the deity whom he is going to praise.
Sama Veda, Chandogya Upanishad I, III – Meditation on the Udgitha as the Sun and the Vyana, 9
He (the udgatri priest) should meditate on the metre in which he is going to chant the praise; he should meditate on the hymn by which he is going to chant the praise.
Sama Veda, Chandogya Upanishad I, III – Meditation on the Udgitha as the Sun and the Vyana, 10
