First Steps Toward Unity
As a means of promoting religious unity Baha'u'llah advocates the utmost charity and tolerance, and calls on His followers to "consort with the people of all religions with joy and gladness." In His last Will and Testament He says: (79:1)

Contention and conflict hath He strictly forbidding in His book (Kitab-i-Aqdas); such is the command of the Lord in this all-highest Revelation - a command which He hath exempted from all annulment and arrayed with the adorning of His confirmation (79:2)

O ye people of the world! The Religion of God is for the sake of love and union; make it not the cause of enmity and conflict.. The hope is cherished, that the people of Baha shall ever turn unto the Hallowed Word: "Lo! All things are of God." - the All-Glorious Word that, like unto water, quencheth the fire of hate and rancor which doth smoulder in hearts and breasts. By this one Word shall the diverse sects of the world attain unto the light of real union; verily the Truth He speaketh, and to the Path He leadeth, and He is the Mighty, the Gracious, the Beauteous. (79:3)

'Abdu'l-Baha says: All must abandon prejudices and must even go to each other's churches and mosques, for, in all of these worshipping places, the Name of God is mentioned. Since all gather to worship God, what difference is there? None of them worship Satan. The Muhammadans must go to the churches of the Christians and the Synagogues of the Jews, and vice versa, the others must go to the Muhammadan Mosques. They hold aloof from one another merely because of unfounded prejudices and dogmas. In America I went to the Jewish Synagogues, which are similar to the Christian Churches, and I saw them worshipping God everywhere (79:4)

In many of these places I spoke about the original foundations of the divine religions, and I explained to them the proofs of the validity of the divine prophets and of the Holy Manifestations. I encouraged them to do away with blind imitations. All of the leaders must, likewise, go to each other's Churches and speak of the foundation and of the fundamental principles of the divine religions. In the utmost unity and harmony they must worship God, in the worshipping places of one another, and must abandon fanaticism. (79:5)

Were even these first steps accomplished and a state of friendly mutual tolerance established between the various religious sects, what a wonderful change would be brought about in the world! In order that real unity may be achieved, however, something more than this is required. For the disease of sectarianism, tolerance is a valuable palliative, but it is not a radical cure. It does not remove the cause of the trouble. (79:6)

The Problem of Authority
The different religious communities have failed to unite in the past, because the adherents of each have regarded the Founder of their own community as the one supreme authority, and His law as the divine law. Any Prophet Who proclaimed a different message was, therefore, regarded as an enemy of the truth. The different sects of each community have separated for similar reasons. The adherents of each have accepted some subordinate authority and regarded some particular version or interpretation of the Founder's Message as the One True Faith, and all others as wrong. It is obvious that while this state of matters exists no true unity is possible. Baha'u'llah, on the other hand, teaches that all the Prophets were bearers of authentic messages from God; that each in His day gave the highest teachings of all are essentially in harmony, and are parts of a great plan for the education and the unification of humanity. He calls on the people of all denominations to show their reverence for their Prophets by devoting their lives to the accomplishment of that unity for which all the Prophets labored and suffered. In His letter to Queen Victoria He likens the world to a sick man whose malady is aggravated because he has fallen into the hands of unskilled physicians; and He tells how the remedy may be effected: (80:1)

That which the Lord hath ordained as the sovereign remedy and mightiest instrument for the healing of all the world is the union of all its peoples in one universal Cause, one common Faith. This can in no wise be achieved except through the power of a skilled, an all-powerful and inspired Physician. This, verily, is the truth, and all else naught but error. - Gleanings from the Writings of Baha'u'llah, p. 255. (80:2)

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