This is is very thorough and well argued article from a brilliant young scholar, Gordon Dakota Arnold. He sympathizes with the perspective of more accommodation of traditional, conservative Christianity in public life. The article is a good reminder that America's Founders weren't always on the same page. But we can make observations like James Madison and Thomas Jefferson had a particular vision of church-state relations that was more secular and "separation of church and state" oriented. This has been called the "Virginia view" because Madison and Jefferson were both from Virginia and saw their vision validated in the Virginia Statute for Religious Freedom.
But there were other perspectives; the "Massachusetts view" was most notably articulated by George Washington and John Adams and permitted more expression of religion in public life and more interplay between church and state.
But onto Arnold's article. A taste:
Was Madison a Christian?
It is quite likely that the beginning of Madison’s rejection of Christian nationalism is found in a rejection of orthodox Christianity more generally. Like George Washington, Madison was meticulous in his effort to keep his precise religious beliefs private, and he shied away from discussing theology or religious doctrine in all of his private correspondence. Whereas Thomas Jefferson and John Adams left ample evidence in their writings that they rejected the divine origins of orthodox Christianity, Madison’s papers never explicitly denounced doctrines such as the divinity of Jesus Christ or the resurrection.11 And yet, it is a mistake to rely upon arguments from silence as a means of bolstering Madison’s claims to orthodoxy. In 1774, when Madison the youth was studying under the Rev. John Witherspoon and considering a career in ministry, he praised the “advocates of the cause of Christ.”12 But after this, references to Jesus Christ in his private correspondence disappeared and he appeared to approach religion with more indifference. As an adult, Madison is said to have refused to kneel for prayer, and though he sometimes attended an Episcopal Church, he never joined it and never participated in holy communion.13 Friends of Madison, such as the Bishop William Meade, attested to his unbelief,14 and George Ticknor recounted a conversation he had with the President in 1815 wherein he “intimated to me his own regard for Unitarian doctrines.”15
But more disturbing than Madison’s apparent shift away from the evangelical theology of his youth is the sense one gets while reading his corpus that his final position entailed more hostility towards traditional Christianity than has often been acknowledged. As early as 1772, Madison included a striking note in his Commonplace Book, quoting from the Cardinal de Retz: “Nothing is more Subject to Delusion than Piety. All manner of Errors creep and hide themselves under that Veil. Piety takes for sacred all her imaginations of what sort soever.”16 Throughout Madison’s long career, he often returned to this theme about the political dangers of piety and religion. “Religious bondage,” he said to his friend William Bradford, “shackles and debilitates the mind and unfits it for every noble enterprize every expanded prospect” [sic].17 While Madison in one instance referred in passing to Christianity as the “best & purest religion,” it is likely that he, like his friend Thomas Jefferson, primarily praised it with a view towards its ethical precepts—precepts accessible to unaided, natural reason—and emphatically not its doctrinal claims uncovered within divine revelation.18 In fact, Madison thought that doctrinal orthodoxy needed to be eliminated in order to further the cause of progress and enlightenment. In a letter to Thomas Jefferson, Madison complained about “Sectarian Seminaries” in Virginia—almost certainly alluding to Calvinist or Reformed institutions of learning—and their incorporation into the Virginia state charter on the grounds that this would empower churches of “any creed however absurd or contrary to that of a more enlightened age.”19 Doctrines must shift and change with the times, and any attempt to ground the nation in a static doctrine of Christianity is a threat to progress.
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Madison and the Great Divorce of Christianity and Politics
Because he believed that religion is essentially a passion that causes rather than discourages faction, Madison also contended that it needed to be pacified for liberty to be preserved. The primary method of solving the political problem of Christianity was to encourage religious diversity and foster disunity. As Madison’s friend, neighbor, and first biographer William Cabell Rives reported, the President was fond of quoting Voltaire’s maxim that “if one religion only were allowed in England, the government would possibly be arbitrary; if there were but two, the people would cut each other’s throats; but, as there are such a multitude, they all live happy and in peace.”30 And Madison himself left no doubt that these were exactly his sentiments. He spoke in Federalist no. 51 of how the “multiplicity of sects” was the only security for the preservation of “religious rights.”31 In a letter to Thomas Jefferson, Madison celebrated the fact that the “mutual hatred” of Virginia’s Christian denominations “has been much inflamed.”32 He added: “I am far from being sorry for it, as a coalition between them could alone endanger our religious rights.”33 Where the Apostle Paul spoke of the need for harmony, unity, and love within the body of Christ, Madison preferred that the church be characterized by disarray, discord, and faction. Only then would Christianity fail to mobilize itself as a political force, and only then would the natural rights of individuals be safe from a majority faction. Madison’s view, too, contrasts with the more Pauline beliefs of George Washington, who celebrated the “harmony and Brotherly Love which characterizes the clergy of different denominations” because it further substantiated his conviction that “Religion and Morality are the essential pillars of civil society.”34