The earliest records of spiritual research are to be found in the Rig-Veda Samhita, which consists of hymns, or Mantras, addressed to gods, or Devas, who are considered as deities or divinities capable of controlling the destinies of people. The history of the growth of the religious consciousness from its incipiency to its mightiest comprehension can be read between the lines of these sacred prayers, the Mantras of the Veda. The trend of beholding the manifold as expressions of the One, and the One as revealing itself in the many, is unmistakably traceable to the hymns of the Rig-Veda. Through a succession of this unfolding movement of religious visualisation, the Veda-Samhita proclaims its final word on the nature of Reality. The Purusha-Sukta, or the hymn of the Cosmic Person, embodies in itself the most magnificent description of the spiritual unity of the cosmos. In the spirit of a great attainment the Seers of the Veda explored the majesty of the universe as an embodiment of a Supreme Intelligence and Power hiddenly present everywhere and controlling all things as the Soul, the very Self of everything. From the recognition of an other-than-the world location of numberless deities, the vision moves to the glorious presence of scintillating gods animating all creation, who are, further, beheld as the twinkling eyes and thoughts of a boundless God in whom they are all comprehended in a single instantaneous and divisionless entirety. In the Purusha-Sukta is given, perhaps, the earliest complete presentation of the nature of the Ultimate Reality as both transcendent and immanent. The all-encompassing Purusha, who is portrayed as all heads, all eyes and all limbs, everywhere, envelopes and permeates creation from all sides and stands above it as the glorious immortal. The Purusha is all that was, is, and shall be. The universe is a small fraction of Him, for He ranges above it in the infinitude of His glory. From Him proceeds the original creative Will, later identified with Brahma, Hiranyagarbha, or Prajapati, by which this vast universe was projected in space and time. The Purusha-Sukta proclaims once and for all the oneness of God, the universality of religion, the organic inseparability of the constituents of social structure, and the utter imperative of it being not only possible but necessary for everyone to realise in direct experience the Supreme Being, the Infinite Person, in an act of inner awakening. The Seer of the Veda loved humanity and creation as much as he loved the Almighty God.

The Nasadiya-Sukta of the Rig-Veda proclaims, for the first time, intimations of the Seer's sounding the depths of being. The astounding vision of the Transcendent by the relative is the apparent theme of this famous hymn. The Ultimate State is here depicted as not capable of being designated either as existence or as non-existence, for there was none, then, to perceive it, before the manifestation of the heaven and the earth. There was only an indescribable stillness as it were, deep in its content and defying approach to it by anyone. The Sukta says that there was neither death nor immortality, for there was no differentiation whatsoever. Naturally, there was neither day nor night. There was only That One Presence, throbbing in all splendour and glory but appearing as darkness to the eye that would like to behold it. There was nothing second to it; It alone was. From It creation arose. However, how it all happened no one can say, for everyone came after creation. This is the central point of the Nasadiya Hymn, varied forms of the development of which lead to many ramifications of philosophic and religious meditations, in the Upanishads and the later established forms of religion. In a famous Mantra, the Rig-Veda declares that "Existence (or Reality) is One, though the wise ones call It by various epithets like Indra, Mitra, Varuna, Agni, Yama, Vayu", thus unifying all the gods in a singleness of Being.

The Rudra Adhyaya, or the Satarudriya, a hymn of the Yajur Veda, is a thrilling invocation of the Supreme Being as Rudra-Siva, wherein He is addressed in all the visible and conceivable forms in creation. The Almighty Lord is the big and the small, the gross and the subtle, the low and the high, the distant and the near, the visible and the invisible, what is and what is not. Every type of individuality, form and action, every category of living species, everything that is animate or inanimate, all that is gracious and all that is frightening, and every deed that man is capable of doing, all things through which nature works and is revealed, are adored as the forms of Siva, or Rudra, presenting an impossible method of approach to the Impossible God of the Universe.

The quintessence of the Veda Samhitas, and their hidden purport is said to be codified in the Upanishads, which unveil Truth without the embellishments and formative features through which it was seen in the Samhitas. The Upanishads hold that the pleasures of the senses are ephemeral, as they wear away one's energies and tend to one's destruction. Even the longest life with the greatest pleasure is worth nothing. The only desirable aim in this world is the knowledge of the Self, the Atman. The pleasant is one thing and the good is another. Both these come to a man together for acceptance. The wise one discriminates between the two and chooses the good rather than the pleasant. The foolish one chooses the pleasant and falls into the net of widespread death. By knowing It Reality, everything is known at once. One who knows It becomes It. Reality transcends the three states of waking, dream and deep sleep. It is the cessation of all phenomena, the peaceful, the blessed, the non-dual. It is Truth, Knowledge, Infinity. One possesses all things simultaneously and becomes all things at once, and enjoys all things instantaneously, who realises Brahman as identical with one's own being.

The Infinite alone is bliss, there is no bliss in the small and the finite. Where one sees nothing else, hears nothing else, understands nothing else - that is the Infinite. Where one sees something else, hears something else, understands something else - that is the finite. The Infinite is the immortal. The finite is the mortal. The Infinite is in front, behind, to the right, to the left, above, below and everywhere. It is all this at the same time. For one who knows this, everything springs from his very Self. The universe, manifest as well as unmanifest, arises for him spontaneously from his Self and serves him without limitation of time or place.

No one loves an object for its own sake. All love is an inspiration come finally from love of the Universal Self. Things are dear because of the Infinite that peeps through them. The Infinite summons the Infinite in the perception of the beloved. Persons and things are not dear for their own sake. Though all love has a selfish origin in the world, it has a transcendent meaning above the phase of the seer and the seen. Anyone who, by an error, regards anything as being outside oneself, shall lose that thing, whatever it may be.

Where there is duality, as it were, there one sees the other, smells the other, speaks to the other, tastes the other, touches the other, thinks the other, understands the other. But, where the One alone is, who can see what, and by what, who can hear, smell, speak, taste, touch, think and understand what by what? How can one know that by which alone one knows all these things? How can one know the knower? This is the great admonition, this is the treasure-house of knowledge. If one were to give the whole earth as a gift for the sake of this knowledge, one should regard this knowledge as greater than that. Lo, this is greater than all things. Whosoever has his Self awakened within himself commensurate with all things, he is verily equivalent to the Creator of the universe, he becomes the doer of all things; this universe is his, nay, he himself is the universe.

The sacred lore of the Veda consists of the body of hymns known as Samhitas; expository texts on the rituals and methods of sacrifice known as Brahmanas; sylvan texts for contemplation in retreat known as Aranyakas, and mystical meditations known as the Upanishads. The Vedic knowledge is a blend of the highest kind of education of the inner man, through which one is enabled to possess in practical life and experience not only the glories and joys of the world in their fullest measure, but also to transform oneself into an embodiment of the highest form of righteousness and justice, and a moving representation, as it were, of God, the Almighty.