Some Ans. Questions 2014 by -'Abdu'l-Bahá- 1 Para

Moreover, it is necessary that the signs of the perfections of the spirit appear in this world, that the realm of creation may bring forth endless fruits, and that this body of the contingent world may receive life and manifest the divine bounties. So, for example, the rays of the sun must shine upon the earth and its heat must nurture all earthly beings; if the rays and heat of the sun were not to reach the earth, it would remain idle and desolate and its development would be arrested. Likewise, were the perfections of the spirit not to appear in this world, it would become dark and wholly animalistic. It is through the appearance of the spirit in the material body that this world is illumined. Just as the spirit of man is the cause of the life of his body, so is the whole world even as a body and man as its spirit. If man did not exist, if the perfections of the spirit were not manifested and the light of the mind were not shining in this world, it would be like a body without a spirit (52:3)

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