Paris, October 31st, 1912
The Divine Reality is Unthinkable, Limitless, Eternal, Immortal and Invisible.
The world of creation is bound by natural law, finite and mortal.
The Infinite Reality cannot be said to ascend or descend. It is beyond the understanding of man, and cannot be described in terms which apply to the phenomenal sphere of the created world.
Man, then, is in extreme need of the only Power by which he is able to receive help from the Divine Reality, that Power alone bringing him into contact with the Source of all life.
An intermediary is needed to bring two extremes into relation with each other. Riches and poverty, plenty and need: without an intermediary power there could be no relation between these pairs of opposites.
So we can say there must be a Mediator between God and Man, and this is none other than the Holy Spirit, which brings the created earth into relation with the 'Unthinkable One', the Divine Reality.
The Divine Reality may be likened to the sun and the Holy Spirit to the rays of the sun. As the rays of the sun bring the light and warmth of the sun to the earth, giving life to all created beings, so do the 'Manifestations'[Manifestations of God] bring the power of the Holy Spirit from the Divine Sun of Reality to give light and life to the souls of men.
Behold, there is an intermediary necessary between the sun and the earth; the sun does not descend to the earth, neither does the earth ascend to the sun. This contact is made by the rays of the sun which bring light and warmth and heat.
The Holy Spirit is the Light from the Sun of Truth bringing, by its infinite power, life and illumination to all mankind, flooding all souls with Divine Radiance, conveying the blessings of God's Mercy to the whole world. The earth, without the medium of the warmth and light of the rays of the sun, could receive no benefits from the sun.
Likewise the Holy Spirit is the very cause of the life of man; without the Holy Spirit he would have no intellect, he would be unable to acquire his scientific knowledge by which his great influence over the rest of creation is gained. The illumination of the Holy Spirit gives to man the power of thought, and enables him to make discoveries by which he bends the laws of nature to his will.
The Holy Spirit it is which, through the mediation of the Prophets of God, teaches spiritual virtues to man and enables him to attain Eternal Life.
All these blessings are brought to man by the Holy Spirit; therefore we can understand that the Holy Spirit is the Intermediary between the Creator and the created. The light and heat of the sun cause the earth to be fruitful, and create life in all things that grow; and the Holy Spirit quickens the souls of men.
The two great apostles, St Peter and St John the Evangelist, were once simple, humble workmen, toiling for their daily bread. By the Power of the Holy Spirit their souls were illumined, and they received the eternal blessings of the Lord Christ. (‘Abdu'l-Baha, Paris Talks)
… Holy Spirit is the mediator between God and His creatures. It is like a mirror facing the sun. As the pure mirror receives light from the sun and transmits this bounty to others, so the Holy Spirit is the mediator of the Holy Light from the Sun of Reality, which it gives to the sanctified realities. It is adorned with all the divine perfections. Every time it appears, the world is renewed, and a new cycle is founded. The body of the world of humanity puts on a new garment. It can be compared to the spring; whenever it comes, the world passes from one condition to another. Through the advent of the season of spring the black earth and the fields and wildernesses will become verdant and blooming, and all sorts of flowers and sweet-scented herbs will grow; the trees will have new life, and new fruits will appear, and a new cycle is founded. The appearance of the Holy Spirit is like this. Whenever it appears, it renews the world of humanity and gives a new spirit to the human realities: it arrays the world of existence in a praiseworthy garment, dispels the darkness of ignorance, and causes the radiation of the light of perfections. Christ with this power has renewed this cycle; the heavenly spring with the utmost freshness and sweetness spread its tent in the world of humanity, and the life-giving breeze perfumed the nostrils of the enlightened ones.
In the same way, the appearance of Bahá'u'lláh was like a new springtime which appeared with holy breezes, with the hosts of everlasting life, and with heavenly power. It established the Throne of the Divine Kingdom in the center of the world and, by the power of the Holy Spirit, revived souls and established a new cycle. (‘Abdu'l-Baha, Some Answered Questions)