But some souls are weak; we must endeavor to strengthen them. Some are ignorant, uninformed of the bounties of God; we must strive to make them knowing. Some are ailing; we must seek to restore them to health. Some are immature as children; they must be trained and assisted to attain maturity. We nurse the sick in tenderness and the kindly spirit of love; we do not despise them because they are ill. Therefore, we must exercise extreme patience, sympathy and love toward all mankind, considering no soul as rejected. If we look upon a soul as rejected, we have disobeyed the teachings of God. God is loving to all. Shall we be unjust or unkind to anyone? Is this allowable in the sight of God? God provides for all. Is it befitting for us to prevent the flow of His merciful provisions for mankind? God has created all in His image and likeness. Shall we manifest hatred for His creatures and servants? This would be contrary to the will of God and according to the will of Satan, by which we mean the natural inclinations of the lower nature. This lower nature in man is symbolized as Satan—the evil ego within us, not an evil personality outside.
(‘Abdu’l-Bahá, The Promulgation of Universal Peace, p. 286-287)
There is, unfortunately, no way that one can force his own good upon a man. The element of free will is there, and all we believers—and even the Manifestation of God Himself—can do is to offer the truth to mankind. If the people of the world persist, as they seem to be doing, in their blind materialism, they must bear the consequences in a prolongation of their present condition, and even a worsening of it. Our duty as Bahá’ís is to build up such a love and unity within our own ranks that the people will be attracted by this example to the Cause. We also must teach all we can and strengthen the Bahá’í Community in the administration. But more we cannot do to avert the great sufferings which seemingly still lie ahead of the world in its present evil state.
(Shoghi Effendi, Lights of Guidance, p. 113)