“‘ABDU’L-BAHÁ WILL SPEAK upon the oneness of humanity,” Reverend Leon Harvey told to his congregation at All Souls Unitarian Church in Brooklyn. “It is a great gospel,” he said. “Many have dreamed of it, but ‘Abdu’l-Bahá has lived it.”

The congregation at All Souls was one of the largest in the city. During its hundred-year history it had counted among its members some of New York’s most prominent reformers and cultural figures, including novelist Herman Melville. It was founded in 1819 under the Congregationalist banner, but by the late 1800s had become a Universalist Unitarian church – a movement with roots in Christianity, which accepted people of every religious background, unified by a dedication to spiritual growth and a commitment to serving the local community.

Reverend Harvey was pleased that he had assembled such a large crowd on one of the hottest days in memory. He began with a prayer: “We thank Thee for him whom we shall hear this morning and pray that whatever may come to us may not fall upon barren soil.”

Then ‘Abdu’l-Bahá took the pulpit and began. “In this great century the most important accomplishment is the unity of mankind,” he announced, “it has now become the paramount issue and question in the religious and political conditions of the world.”

‘Abdu’l-Bahá’s talk followed a similar outline as many he had given in churches over the past three months. However, on this Sunday he was particularly forthright, even blunt. “Consult history,” he said, “you will find a continuous record of war brought about by religious, sectarian, patriotic, racial and political causes.” He was particularly hard on religion, stating simply: “The greatest cause of human alienation has been religion. . .”

But ‘Abdu’l-Bahá’s subject was “the oneness of humanity” and he intended to point the way forward. He invoked a metaphor from his father’s writings. “Ye are all the leaves of one tree,” Bahá’u’lláh had written. ‘Abdu’l-Bahá accepted that people were imperfect, and that there were seemingly legitimate reasons for discord. But he asked his audience to focus on humanity’s common foundation.

“Humanity shares in common the intellectual and spiritual faculties of a created endowment,” ‘Abdu’l-Bahá said. “This equal participation in the physical, intellectual and spiritual problems of human existence is a valid basis for the unification of mankind.”

In considering the effects of disunity, ‘Abdu’l-Bahá invoked the image of the family. “Consider the harmful effect of discord and dissension in a family; then reflect upon the favors and blessings which descend upon that family when unity exists among its various members.” He concluded: “What incalculable benefits and blessings would descend upon the great human family if unity and brotherhood were established!”

Speaking of disagreements over religion, ‘Abdu’l-Bahá again quoted from his father, who had said: “If religion and faith are the causes of enmity and sedition it is far better to be non-religious.” Then, as if to drive home the point, ‘Abdu’l-Bahá added: “When we make the remedy the cause of disease it would be better to do without the remedy.”

‘Abdu’l-Bahá left his audience with a call to action. “Now in this radiant century let us try to do the will of God that we may be rescued from these things of darkness and come forth into the boundless illumination of heaven, shunning division and welcoming the divine oneness of humanity.”