Archibald Bruce (1746-1816) was pastor of a single congregation, the Secession church in the hamlet of Whitburn, Linlithgowshire, Scotland from 1768 until his death. In 1786 he was elected by his peers to be Professor of Divinity for the General Associate Synod. Among the young men who sat under Bruce's instruction in the provincial theological hall at Whitburn were Thomas M'Crie (Bruce's successor in the chair), George Stevenson, Robert Shaw (who followed Bruce as pastor in Whitburn, and wrote a standard Scottish exposition of the Westminster Confession), and "Rabbi" John Duncan.
Bruce defended the propriety of a national acknowledgment of religion, as sanctioned by Scripture. In 1804 Bruce's synod changed its testimony on this point, and Bruce's protest led to his expulsion in 1806, when together with Thomas M'Crie and four other ministers, Bruce formed the Constitutional Associate Presbytery. In 1807 M'Crie published his Statement of the Difference, which is one of the most distinguished expositions of the Westminster Confession's teaching respecting a national acknowledgment of religion; one chapter of the work is based on notes provided by Bruce. In 1817, M'Crie edited Bruce's lectures for posthumous publication.
Archibald Bruce wrote a flood of books on such matters as the establishment principle, the freedom of the press, the evil of England's royal supremacy in the church, the civil loyalty of Presbyterian dissenters who lobbied for political reform, and the history of religious festivals. M'Crie eulogized Bruce in the following terms: "For solidity and perspicacity of judgment joined to a lively imagination, for the power of patient investigation, of carefully discriminating between truth and error, and of guarding against extremes on the right hand as well as the left, Mr. Bruce has been equaled by few, if any, of those who have occupied the chair of divinity, either in late or in former times."
The following material is from Bruce's A Historico-Politico-Ecclesiastical Dissertation on the Supremacy of Civil Powers in Matters of Religion, Edinburgh 1802.
In consequence of the laws delivered at Sinai, the church of God assumed a more regular and settled form. It was then changed from the patriarchal state to a national establishment. The whole people were taken into a peculiar religious covenant, and became "a kingdom of priests" to the Lord. The many ceremonies and external services then added, served to preserve them a distinct people, and chiefly respected their public national worship. A regular priesthood was selected, and divinely ordained, not indiscriminately out of any nation or tribe, but one whole tribe of Israel was consecrated instead of the first-born, to act "in things pertaining to God," not for a single house, city, or tribe, but in name of the whole people incorporated into one. Some things that before were matters of liberty, ceased from that time to be so, when the authority of the divine legislator had interposed, and ordered them otherwise. This was particularly the case with respect to the separation of sacred persons and offices.
There was, indeed, at the same time, a state or political connection formed; and the nature of the religion appointed, necessarily required a peculiar polity adapted to it, without which it could not have nationally subsisted. Such a constitution as should answer this principal end, divine wisdom alone could dictate, and the divine hand alone could support. A code of civil and judiciary laws, prescribing the fundamental articles of the national government, was accordingly added to the ceremonial, as the ceremonial had been annexed to the moral; each serving its particular purpose, under that singular and complex government, which, after some Jewish writers, is usually denominated, and not improperly, a Theocracy. The term implies, that the government was divine, quite different from all the other human plans of policy, by which every other people would have been governed. And such it evidently was; the whole complex system of laws, the judicial, as well as the ceremonial and moral, having the same common origin, being enacted by the immediate authority of heaven, in subserviency to one great ultimate end, which was truly divine; all of them to be observed under a sense of the immediate commands, promises, and threatenings of the divine legislator, in the observance or violation of which he was, in a peculiar manner, to interest himself; and in it he was to manifest his continual superintendence over their affairs, not only by his ordinary providence, and the agency of his visible ministers, but by direct interference as often as he saw meet.
This appears briefly to be the most proper notion of the Theocracy, which some have altogether denied, and as to which others have formed such confused theories, pregnant with many absurd consequences. Though the Theocracy comprehended the whole extent of the divine legislation and administration among the Jews, respecting things civil, moral, and religious, yet this distinguishing name more properly belongs to it, considered as a peculiar form of political or national government; for a divine government by moral laws, (though these were in a peculiar way delivered to that people), was not confined to any land or age, but God is King of all the earth, and continues to reign for ever; and the institution of a system of religion by immediate revelation, or the erection of a church-state by supernatural agency, and the continual government of it by laws immediately delivered from heaven, was not peculiar to the times of the Jewish Theocracy. The Christian church, in this sense, is a real Theocracy, or, which is the same thing, a Christocracy; on which account, it is usually designed in the New Testament, the kingdom or reign of God, of Christ, and of heaven.
Much confusion and wrangling, indeed, is ready to arise on this subject, from not only using the terms, but rigidly adhering to the ideas, ordinarily affixed, in modern times, to church and state, when we would judge of the nature and distinct parts of that ancient establishment. For in vain will we search either for a civil polity, or a church-state, strictly and exactly corresponding to modern ideas of these; or for the same distinctions, in all respects, between them, as may have obtained, or ought to be observed, under the Christian law, in a government that was an unique, never to have a parallel, and in ages when no Christian church, in its constituted form, yet existed. Much caution is therefore necessary in all reasonings from the Jewish model, either when they are applied to the affair of political laws, or the constitution and administration in a Christian church; as the peculiarities of that establishment can never with propriety be appealed to, as a reason for adopting or condemning any thing in either, except in cases wherein there may be some evident, though remote, analogy.
Upon the whole, we may conclude, that the office and acts of Jewish kings and magistrates, so far as founded on the principles of natural equity, and regulated by the common law, and directed to the ordinary ends of civil government, still furnish an imitable precedent, for all who bear rule in a commonwealth. That the exercise of their office in reference to the honor of God, and the maintenance of his worship as then settled, within their line, without encroaching either on God's supreme prerogative, or the rights of his immediate ministers, affords an analogical proof of the right and duty of Christian rulers, to promote not only the general interests of religion, but also to countenance and support, under similar restrictions, that particular system of religion, that, by positive institution, has superseded the Jewish; paying still due attention to the changes that have been introduced, and the great differences between these two systems. But any authority assumed by Jewish princes, or any acts performed by them in reference to religion, that arose from the peculiarities of their law, or from the influence of an extraordinary spirit, or that were permitted in some extraordinary cases, can never be intended for examples to ordinary rulers in any other nation. The Jewish ritual, together with the peculiar national polity connected with it, having been abolished, nothing of the same kind with the latter was prescribed, in or along with the Christian system, that this might be equally adapted to any nation, and any particular form of lawful civil government.