In Anthroposophy we learn that Zarathustra was the great teacher in the Persian culture period. We must realise that Zarathustra didn't live a few centuries before Christ, but far earlier, eight thousand years ago. I quote here from a lecture of Rudolf Steiner from 1911. He gives a clear impression of this doctrine of Zarathustra.
'When we turn our attention to Zarathustra, we must look back over an infinitely long period of time. It is true that certain modern investigators have fixed the date of Zarathustra as contemporary with that of Buddha, which would mean that he lived some five or six centuries before the Christian era. It is however significant that our modern historians, after careful investigation of the traditions referring to Zarathustra, have been obliged to indicate that the personality hidden beneath the name of “Zarathustra,” the original founder of the Persian religion, must be placed a great many centuries before Buddha. Greek historians have repeatedly pointed out that Zarathustra must have lived about five or six thousand years before the Trojan War.
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Zarathustra lived at least eight thousand years before our present era, and the gifts to civilisation which poured from his enlightened spirit shine forth clearly across the centuries. Those who penetrate into the inner currents of human evolution can detect them even after this lapse of time. Zarathustra was one of those whose soul had experienced Truth, Wisdom and Intuition to an extent far transcending the normal consciousness of the age. In that part of the Earth which later on was known as the Persian Empire, Zarathustra proclaimed mighty truths from the super-sensible worlds — regions lying far above the normal consciousness of the men of that time.
If we would understand the significance of Zarathustra's teaching, we must realise that his mission was to communicate a certain conception of the universe to one particular section of humanity, while other streams had, as it were, a different mission in human culture. The personality of Zarathustra is all the more interesting to us in that he lived in a part of the world directly adjoining on its South side another land whose people transmitted an entirely different order of spirituality to mankind. I refer to the peoples of India, from whom arose the Vedic poets. The region permeated with the mighty impulse of Zarathustra lies to the North of the land from which the great teaching of Brahma went forth. Zarathustra's message to the world was fundamentally different from the Brahministic teachings of the great leaders of ancient Indian thought. These Indian teachings have come down to us in the Vedas, and in the profound philosophy of the Vedanta, of which the revelations of Buddha represent, as it were, the final splendour.
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Zarathustra taught his disciples to see the Spirit behind every physical phenomenon. The whole civilisation inspired by him was based on this principle. Now it is not enough to say that behind the world of the senses there is the Divine-Spiritual. Man may think he has discovered a great truth here, but it leads to nothing but a vague Pantheism. We may think we express a truth when we say: “God is at work behind every physical phenomenon” — but this is merely a conception of a nebulous spiritual power behind all things physical. A teacher like Zarathustra, who had actually ascended to the spiritual world, did not speak in this abstract and vague terminology to his disciples and his people. He showed that just as individual physical phenomena are different, so the spiritual essence behind them is at one time more evident, at another less. He taught how behind the physical Sun — the origin of all life and activity — there is the centre of spiritual life.
Let us try to condense into simple language the doctrines which Zarathustra tried to inculcate into his disciples. He spoke thus: “Man, as we perceive him, is not merely composed of a physical body, for this physical body is but the outer manifestation of the Spirit. Just as the physical body is nothing but the manifested crystallisation of the Spiritual in man, so the Sun, in so far as it is a body of luminous matter, is nothing but the external body of a spiritual Sun.” The spiritual part of man is spoken of as the “Aura” — or “Ahura,” to use the old expression — in distinction to his physical body and in the same sense the spiritual part of the physical Sun may be called the “Great Aura,” for it is all-embracing. Zarathustra called that which lies behind the physical Sun, Aura Mazda or Ahura Mazdao — the Great Aura. With this spiritual essence behind the Sun, all spiritual experiences and conditions are bound up, just as the existence and well-being of plants, animals and all that lives on Earth are bound up with the physical Sun. Behind the physical Sun lives the spiritual Lord and Creator, Ahura Mazdao. This is the derivation of the name “Ormuzd,” Spirit of Light. While the Indians searched mystically in the inner self to find Brahma, the Eternal, shining like a luminous centre in man, Zarathustra pointed his disciples to the great periphery, showing them that the mighty Spirit of the Sun, Ahura Mazdao, the Spirit of Light, dwelt in the physical body of the Sun. Ahura Mazdao has to face his enemy — Ahriman, the Spirit of Darkness — just as man, who bears within himself the enemies of his good impulses, strives to raise his real spiritual being to perfection and has to battle against his lower passions, desires, and the delusive images of lying and falsehood.
Zarathustra was able to transmute his conception of the universe from mere doctrine into real feeling, real vision. And so he was able to teach his disciples that within them was an active principle of perfection. Whatever their development might be at the time, they were taught to realise that this principle of perfection could raise them to higher and higher stages of existence. They were taught that passions and desires, lying and deceit within the soul lead to imperfection. Zarathustra taught of the attacks made upon Ahura Mazdao in the outer world by the principle of imperfection, by the evil which casts shadow into the light, by Angra Mainyus — Ahriman.
Zarathustra's disciples were thus enabled to realise that the great universe is reflected in each individual. The real significance of this doctrine lay, not in its theoretical concepts and ideas but in the feeling it called forth in man — a feeling which taught him of his relationship to the universe and made him able to say: “Here I stand — a little world, but a little world which is a replica of the great world. In human beings, the principle of perfection is opposed by evil; in the great universe, Ormuzd and Ahriman face one another. The whole universe is, as it were, a man grown immeasurably great and the highest human forces are Ahura Mazdao — their enemy, Ahriman.”
If man directs his attention truly to the physical world he must finally discover that all phenomena are part of the great cosmic process; he is filled with awe when spectro-analysis reveals the fact that the same substances which exist on Earth exist also on the farthest stars. In the light of Zarathustra's teaching, man felt himself in his spiritual being, part of the Spirit of the whole Cosmos; he felt himself emanating from this Spirit. Herein lies the great significance of the doctrine. (GA 60, Zarathustra, 19.01.11)
Zarathustra
The evil in the teaching of Zarathustra by Mieke Mosmuller