God's purpose in sending His Prophets unto men is twofold. The first is to liberate the children of men from the darkness of ignorance, and guide them to the light of true understanding. The second is to ensure the peace and tranquillity of mankind, and provide all the means by which they can be established. (Baha’u’llah, ‘Gleanings from the Writings of Bahá'u'lláh’ pp. 79-80; The Compilation of Compilations vol II, p. 151)
The well-being of mankind, its peace and security, are unattainable unless and until its unity is firmly established. This unity can never be achieved so long as the counsels which the Pen of the Most High hath revealed are suffered to pass unheeded. (Baha’u’llah, ‘Gleanings from the Writings of Bahá'u'lláh’, p. 286; The Compilation of Compilations vol II, p. 153)