It is only by the breath of the Holy Spirit that spiritual development can come about. No matter how the material world may progress, no matter how splendidly it may adorn itself, it can never be anything but a lifeless body unless the soul is within, for it is the soul that animates the body; the body alone has no real significance. Deprived of the blessings of the Holy Spirit the material body would be inert.
- ‘Abdu’l-Baha (From a talk; ‘Paris Talks: Addresses given by 'Abdu'l-Bahá in Paris in 1911-1912’)