From the beginning of His stupendous Mission, Baha'u'llah urged upon the attention of nations the necessity of ordering human affairs in such a way as to bring into being a world unified in all the essential aspects of its life. In unnumbered verses and Tablets He repeatedly and variously declared the 'progress of the world' and the 'development of nations' as being among the ordinances of God for this day. The oneness of mankind, which is at once the operating principle and ultimate goal of His Revelation, implies the achievement of a dynamic coherence between the spiritual and practical requirements of life on earth. The indispensability of this coherence is unmistakably illustrated in His ordination of the Mashriqu’l-Adhkar, the spiritual centre of every Baha'i community round which must flourish dependencies dedicated to the social, humanitarian, educational and scientific advancement of mankind.
(The Universal House of Justice, from a letter to the Bahá'ís of the World dated October 20, 1983; compilation: ‘Lights of Guidance’)