For brevity let me reproduce below some of the salient statements from this paper. The authors of the book tell us that these are the essentials of the teachings of Jesus Christ on the subject topic when he was incarnated on earth as a human being some 2000 years ago:
The kingdoms of this world, being material, may often find it necessary to employ physical force in the execution of their laws and for the maintenance of order. In the kingdom of heaven true believers will not resort to the employment of physical force. The kingdom of heaven, being a spiritual brotherhood of the spirit-born sons of God, may be promulgated only by the power of the spirit. This distinction of procedure refers to the relations of the kingdom of believers to the kingdoms of secular government and does not nullify the right of social groups of believers to maintain order in their ranks and administer discipline upon unruly and unworthy members.
There is nothing incompatible between sonship in the spiritual kingdom and citizenship in the secular or civil government. It is the believer’s duty to render to Caesar the things which are Caesar’s and to God the things which are God’s. There cannot be any disagreement between these two requirements, the one being material and the other spiritual, unless it should develop that a Caesar presumes to usurp the prerogatives of God and demand that spiritual homage and supreme worship be rendered to him. In such a case you shall worship only God while you seek to enlighten such misguided earthly rulers and in this way lead them also to the recognition of the Father in heaven. You shall not render spiritual worship to earthly rulers; neither should you employ the physical forces of earthly governments, whose rulers may sometime become believers, in the work of furthering the mission of the spiritual kingdom.
Sonship in the kingdom, from the standpoint of advancing civilization, should assist you in becoming the ideal citizens of the kingdoms of this world since brotherhood and service are the cornerstones of the gospel of the kingdom. The love call of the spiritual kingdom should prove to be the effective destroyer of the hate urge of the unbelieving and war-minded citizens of the earthly kingdoms. But these material-minded sons in darkness will never know of your spiritual light of truth unless you draw very near them with that unselfish social service which is the natural outgrowth of the bearing of the fruits of the spirit in the life experience of each individual believer.
As mortal and material men, you are indeed citizens of the earthly kingdoms, and you should be good citizens, all the better for having become reborn spirit sons of the heavenly kingdom. As faith-enlightened and spirit-liberated sons of the kingdom of heaven, you face a double responsibility of duty to man and duty to God while you voluntarily assume a third and sacred obligation: service to the brotherhood of God-knowing believers.
You may not worship your temporal rulers, and you should not employ temporal power in the furtherance of the spiritual kingdom; but you should manifest the righteous ministry of loving service to believers and unbelievers alike. In the gospel of the kingdom there resides the mighty Spirit of Truth, and presently I will pour out this same spirit upon all flesh. The fruits of the spirit, your sincere and loving service, are the mighty social lever to uplift the races of darkness, and this Spirit of Truth will become your power-multiplying fulcrum.
Display wisdom and exhibit sagacity in your dealings with unbelieving civil rulers. By discretion show yourselves to be expert in ironing out minor disagreements and in adjusting trifling misunderstandings. In every possible way — in everything short of your spiritual allegiance to the rulers of the universe — seek to live peaceably with all men. Be you always as wise as serpents but as harmless as doves.
So long as the rulers of earthly governments seek to exercise the authority of religious dictators, you who believe this gospel can expect only trouble, persecution, and even death. But the very light which you bear to the world, and even the very manner in which you will suffer and die for this gospel of the kingdom, will, in themselves, eventually enlighten the whole world and result in the gradual divorcement of politics and religion. The persistent preaching of this gospel of the kingdom will some day bring to all nations a new and unbelievable liberation, intellectual freedom, and religious liberty.
You must not seek to promulgate truth nor to establish righteousness by the power of civil governments or by the enaction of secular laws. You may always labor to persuade men’s minds, but you must never dare to compel them. You must not forget the great law of human fairness which I have taught you in positive form: Whatsoever you would that men should do to you, do even so to them.
When a kingdom believer is called upon to serve the civil government, let him render such service as a temporal citizen of such a government, albeit such a believer should display in his civil service all of the ordinary traits of citizenship as these have been enhanced by the spiritual enlightenment of the ennobling association of the mind of mortal man with the indwelling spirit of the eternal God. If the unbeliever can qualify as a superior civil servant, you should seriously question whether the roots of truth in your heart have not died from the lack of the living waters of combined spiritual communion and social service. The consciousness of sonship with God should quicken the entire life service of every man, woman, and child who has become the possessor of such a mighty stimulus to all the inherent powers of a human personality.
You are not to be passive mystics or colorless ascetics; you should not become dreamers and drifters, supinely trusting in a fictitious Providence to provide even the necessities of life. You are indeed to be gentle in your dealings with erring mortals, patient in your communication with ignorant men, and forbearing under provocation; but you are also to be valiant in defense of righteousness, mighty in the promulgation of truth, and aggressive in the preaching of this gospel of the kingdom, even to the ends of the earth.
Throughout the vicissitudes of life, remember always to love one another. Do not strive [exert too much to put forth your viewpoints] with men, even with unbelievers. Show mercy even to those who despitefully abuse you. Show yourselves to be loyal citizens, upright artisans, praiseworthy neighbors, devoted kinsmen, understanding parents, and sincere believers in the brotherhood of the Father’s kingdom. And my spirit shall be upon you, now and even to the end of the world.
[Consider reading the full paper-178. Use the online reading link provided in the Urantia-India website]