Whatever exists in the phenomenal universe should be perceived in the light of the consciousness of the supreme Self, Isha, God, Consciousness-Existence-Bliss Absolute. Know that all are impermeated by the divine Reality, God. Thus, renounce matter consciousness. By such renunciation realize the supreme Self. Do not follow the way of the worldly minded.
Man should desire to live the full measure of his life in this world; but he must do so by the performance of his duties, always with the ideal of self-perfection. Thus, his mind will not become a slave to sensory impressions. There is no path other than this to attain self-liberation.
That (Brahman, the Self) is One. The Self is immutable and self-composed. It is transcendental. It is more subtle than the mind. It is beyond the limits of sense perception. It is serene; yet It is more active than the mind or the sense faculties. Because of Its presence, Prana, the life-force, awakens and sustains the functioning powers of the body.
It creates; yet It is transcendental. It is far; yet It is the nearest of all. It resides within all; yet Its presence surrounds and extends beyond all beings.
The wise man perceives all as the manifestation of the One Self, his true Self, and he witnesses the One Self in every being. Because of this realization he hates no one.
(Isha Upanishad, v 1-2, 4-6)
Translated by Swami Premananda, Eight Upanishads