Abdu'l-Baha is basing himself on Baha'u'llah, whose words have been quoted on this thread I think:
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It is incumbent upon the
Sovereigns of the world .... unitedly to hold fast unto this Peace, which is the chief instrument for the protection of all mankind. ... It is
their duty to convene an all-inclusive assembly, which either they themselves or their ministers will attend, and to enforce whatever measures are required to establish unity and concord amongst men.
They must put away the weapons of war, and turn to the instruments of universal reconstruction. Should one king rise up against another, all the
other kings must arise to deter him. Arms and armaments will, then, be no more needed beyond that which is necessary to insure the internal security of their respective countries. If
they attain unto this all-surpassing blessing, the people of each nation will pursue, with tranquillity and contentment, their own occupations, and the groanings and lamentations of most men would be silenced. ... It would be preferable and more fitting that the highly honored
kings themselves should attend such an assembly, and proclaim their edicts. ... In this land [Palestine], every time men are conscripted for the army, a great terror seizeth the people. Every nation augmenteth, each year, its forces, for their ministers of war are insatiable in their desire to add fresh recruits to their battalions. We have learned that the government of Persia -- may God assist them -- have, likewise decided to reinforce their army. In the opinion of this Wronged One a force of one hundred thousand fully-equipped and well-disciplined men would suffice. ... (Baha'u'llah, Epistle to the Son of the Wolf, p. 31)
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There is no reason in principle why Bahais as individuals should not be part of secular government. Along with Catholics and Muslims and others. The separation of church and state does not mean that believers in any religion cannot participate in government, it means (1) that the government does not interfere in matters of religious belief and religious institutions do not get involved in politics and (2) that each individual wears two hats: they are citizens, and they are members of various religious communities including the don't knows and atheists and humanists. When you are doing politics, or government, "God says so" is not an argument. Having believers in some religion, including Bahais, in positions of authority is not a problem (and anyway, excluding believers would be VERY problematical). Abdu'l-Baha says that Bahais in a democracy should participate, as citizens, and he praises the involvement of Bahais and believers in general in public life, because they have two reasons to be virtuous - fear of exposure and fear of God:
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O thou servant of Baha'! Thou hast asked regarding the political affairs. In the United States it is necessary that the citizens shall take part in elections. This is a necessary matter and no excuse from it is possible. My object in telling the believers that they should not interfere in the affairs of government is this: That they should not make any trouble and that they should not move against the opinion of the government, but obedience to the laws and the administration of the commonwealth is necessary. Now, as the government of America is a republican form of government, it is necessary that all the citizens shall take part in the elections of officers and take part in the affairs of the republic.
(Abdu'l-Baha, Tablets of Abdu'l-Baha v2, p. 342)
and
[Words of Abdu’l-Baha on the evening of Saturday 26 Dhu’l-Qacdah 1329 in the house of Monsieur Dreyfus, Paris, 17 November 1911 (my translation from Khitabat-e Abdu’l-Baha page 180,
http://reference.bahai.org/fa/t/ab/KA1/ka1-176.html ) ]
He is God.
In the world of existence, a human being should have the hope of reward and the fear of punishment,
particularly those souls who serve in the government, and have the affairs of the state and the people in their grasp. If the officials of the government do not have such a hope of reward and fear of retribution, they will certainly not behave with justice.
Rewards and punishments are the two poles on which the tent of the world is raised. Thus government officials are held back from committing injustice by the fear of punishment and eager hope for reward.
Consider despotic governments in which there is neither fear of punishment nor hope for rewards. As a result, the affairs of such governments do not pivot upon justice and fairness.
Rewards and punishments are of two sorts. One is political rewards and punishments, and the other is divine rewards and punishments.
It is certain that, if some souls are firmly persuaded of divine rewards and punishments, and they are under the constraints of political rewards and punishments as well, those persons are more perfect, for they will constrained and deterred from practising oppression. If both the fear of God and the fear of retribution are present, that is, if there is both spiritual and political deterrence, of course this is more perfect.
Some government officials, who both fear the chastisement of the state and dread divine torment, naturally observe justice to a greater extent. In particular, those who fear eternal punishment and have hope of everlasting reward: such souls make the greatest possible efforts in thinking how to implement justice, and they are averse to oppression.
For, for those who are firm believers, to commit tyranny is to be visited by divine punishment in the eternal world. Naturally, they will shun oppression and wrong-doing, especially as firm believers, if they dispense justice, will draw near to the threshold of grandeur, gain eternal life, enter into the Kingdom of God, and their faces will be illumined by the lights of divine grace and loving-kindness.
Thus, if government officials are religious, naturally that is better, for they are the manifestations of the fear of God.
My intent with these words is not that religion should have any business in politics. Religion has absolutely no jurisdiction or involvement in politics. For religion is related to spirits and the conscience
while politics is related to the body.
Therefore the leaders of religions should not be involved in political matters, but should devote themselves to rectifying the morals of the people. They admonish and excite the desire and appetite for piety. They sustain the morals of the community, they impart spiritual understandings to the souls, and teach the [religious] sciences, but never get involved in political matters.
Baha’u’llah commands this. In the Gospels, it is written that you should give Caesar what is Caesar’s, and God what is God’s.
The essence of the matter is this: in Iran the righteous Bahai government officials observe the utmost justice, because they fear the wrath of God and hope for the mercy of God.
However there are others who do have no scruples at all. However capable they may be, they never cease their oppressive and negligent acts. This is why Iran is in such difficulties. ...
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