Among His teachings was the declaration of universal peace. ...the teachings of Bahá’u’lláh were not limited to the establishment of universal peace. They embraced many teachings which supplemented and supported that of universal peace.
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In fine, such teachings are numerous. These manifold principles, which constitute the greatest basis for the felicity of mankind and are of the bounties of the Merciful, must be added to the matter of universal peace and combined with it, so that results may accrue. Otherwise the realization of universal peace by itself in the world of mankind is difficult. As the teachings of Bahá’u’lláh are combined with universal peace, they are like a table provided with every kind of fresh and delicious food. Every soul can find, at that table of infinite bounty, that which he desires. If the question is restricted to universal peace alone, the remarkable results which are expected and desired will not be attained. The scope of universal peace must be such that all the communities and religions may find their highest wish realized in it. The teachings of Bahá’u’lláh are such that all the communities of the world, whether religious, political or ethical, ancient or modern, find in them the expression of their highest wish.
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For example, the question of universal peace, about which Bahá’u’lláh says that the Supreme Tribunal must be established: although the League of Nations has been brought into existence, yet it is incapable of establishing universal peace. But the Supreme Tribunal which Bahá’u’lláh has described will fulfil this sacred task with the utmost might and power. And His plan is this: that the national assemblies of each country and nation—that is to say parliaments—should elect two or three persons who are the choicest of that nation, and are well informed concerning international laws and the relations between governments and aware of the essential needs of the world of humanity in this day. The number of these representatives should be in proportion to the number of inhabitants of that country. The election of these souls who are chosen by the national assembly, that is, the parliament, must be confirmed by the upper house, the congress and the cabinet and also by the president or monarch so these persons may be the elected ones of all the nation and the government. The Supreme Tribunal will be composed of these people, and all mankind will thus have a share therein, for every one of these delegates is fully representative of his nation.[1] When the Supreme Tribunal gives a ruling on any international question, either unanimously or by majority rule, there will no longer be any pretext for the plaintiff or ground of objection for the defendant. In case any of the governments or nations, in the execution of the irrefutable decision of the Supreme Tribunal, be negligent or dilatory, the rest of the nations will rise up against it, because all the governments and nations of the world are the supporters of this Supreme Tribunal. Consider what a firm foundation this is! But by a limited and restricted League the purpose will not be realized as it ought and should. This is the truth about the situation, which has been stated....
(“Selections from the Writings of ‘Abdu’l-Bahá”, pp. 297–298, p. 304, pp. 306–307) [21]
22: True civilization will unfurl its banner in the midmost heart of the world...
True civilization will unfurl its banner in the midmost heart of the world whenever a certain number of its distinguished and high-minded sovereigns—the shining exemplars of devotion and determination—shall, for the good and happiness of all mankind, arise, with firm resolve and clear vision, to establish the Cause of Universal Peace. They must make the Cause of Peace the object of general consultation, and seek by every means in their power to establish a Union of the nations of the world. They must conclude a binding treaty and establish a covenant, the provisions of which shall be sound, inviolable and definite. They must proclaim it to all the world and obtain for it the sanction of all the human race. This supreme and noble undertaking—the real source of the peace and well-being of all the world—should be regarded as sacred by all that dwell on earth. All the forces of humanity must be mobilized to ensure the stability and permanence of this Most Great Covenant. In this all-embracing Pact the limits and frontiers of each and every nation should be clearly fixed, the principles underlying the relations of governments towards one another definitely laid down, and all international agreements and obligations ascertained. In like manner, the size of the armaments of every government should be strictly limited, for if the preparations for war and the military forces of any nation should be allowed to increase, they will arouse the suspicion of others. The fundamental principle underlying this solemn Pact should be so fixed that if any government later violate any one of its provisions, all the governments on earth should arise to reduce it to utter submission, nay the human race as a whole should resolve, with every power at its disposal, to destroy that government. Should this greatest of all remedies be applied to the sick body of the world, it will assuredly recover from its ills and will remain eternally safe and secure.