It is a myth perpetuated by secularists that Abraham Lincoln was never a “believer.” Believer in what, exactly? While Lincoln’s unconventional religious views are well-known, the tall tale that Lincoln’s religious views never changed or that he didn’t lean on the support of evangelical Protestants for the eventual abolition of slavery and defense of the Union in the Civil War is not substantiated by Lincoln’s own writings and actions. In his new book, Lincoln’s God: How Faith Transformed a President and a Nation, Joshua Zeitz sympathetically explains Lincoln’s spiritual metamorphosis from skeptic and deist to, at least, a cultural Christian and cultural evangelical.

What though, does Zeitz really mean when he writes that “Lincoln was, arguably, the nation’s first evangelical president”? This sounds something more akin to what evangelical revisionists would say, not a respected historian and journalist of many left-leaning publications. To understand how Lincoln can be plausibly considered an evangelical despite having a faith that was equally “not evangelical by common definition,” Zeitz offers a penetrating and sympathetic overview of the religious environment in the United States as the young country moved closer to disunion and civil war and how this religious environment eventually influenced Lincoln’s own spiritual thinking during the war.

Lincoln was born and raised in an era of emerging religious revivalism, one that saw the old mainline churches of the colonial era slowly lose their cultural importance to new denominations as the country spread westward and experienced a population explosion. Methodists, Baptists, and “New Light” Presbyterians began to surpass the importance of Congregationalists and Episcopalians throughout the United States. Immigrant populations, bringing their own brand of Christian pietism, also spread into the young and energetic country creating a religiously diverse landscape.

The evangelical piety of the 1800s was not the evangelical fundamentalism we conceptualize today, with its strict biblical literalism and emphasis on the “fundamentals” of Christian dogma (something that emerged in the early twentieth century). The evangelicalism of the nineteenth century, Zeitz explains, was, in a sense, reformist and progressive—challenging the old confessions and theological dogmas of the Reformation with a new theology that championed free will, moral and social perfectionism, and a Millennialist eschatology that believed America would be a central player in defeating the world’s many social evils and sins before Christ’s Second Coming, alongside social and political reformism generally revolving around greater rights for women and the abolition of slavery. As Zeitz notes, “the ascendant evangelical churches represented a break with the nation’s colonial past.”

The concept of a secular Lincoln stems from Abe’s law partner from his early life in Springfield, Illinois. William Herndon, although an opponent of slavery and early supporter of the Republican Party, was out of step with the growing revivalism and evangelicalism of the mid-1800s. Herndon’s own skepticism likely drew him close to the young Lincoln who was attempting to break free of the Calvinistic Baptist upbringing of his fatalistic father. Herndon remembered a Lincoln who was hardly a religious man, rejected the divinity of Christ, and believed only in a vague and distant providential God akin to deism. However, the problem with relying on Herndon’s non-Christian Lincoln is that it permits no room for change, and Lincoln’s religious views “changed during the war” as Zeitz carefully shows. The Lincoln of the 1830s was not the Lincoln of the Civil War.

In fact, the road to Lincoln’s religious transformation began with the Kansas-Nebraska Act and the growing confrontation over slavery in the 1850s. The Kansas-Nebraska Act, which repealed the Missouri Compromise and opened the door for western territories to vote on embracing slavery in their territories, caused a firestorm of controversy and violence between pro-slavery and anti-slavery activists. As anti-slavery activists grew in prominence, the nascent evangelical movement took a forceful stand against the expansion of slavery in the new territories.

Just as the Kansas-Nebraska Act aroused the young evangelical movement in America, particularly in the North, to confront the sin of slavery, “the Kansas-Nebraska Act would also stir Abraham Lincoln from a five-year political slumber and bring him more closely into alignment with [Illinois’] growing evangelical churches.” Even though Lincoln initially and largely preserved a humanist and rationalist approach to opposing slavery, he began to periodically use language familiar to Christians—Lincoln had always loved the aesthetical language of the King James Bible even while remaining uncommitted to Christian dogma—and would come to rely on evangelical support for his renewed political hopes which eventually brought him back from obscurity to the presidency. For instance, Lincoln wrote, “Slavery was a great & crying injustice, an enormous national crime and that we could not expect to escape judgement for it.” Lincoln’s use of the language of judgement to reiterate his opposition to slavery was now providential and no longer just humanistic. Lincoln’s political rebirth coincided with a growing reliance on evangelical anti-slavery and abolitionist activists that brought Lincoln closer to evangelical sentiments.

Some might regard this slow embrace of evangelicalism for political support a reflection of Lincoln’s political realism and opportunism. After all, in a nation of religious believers, Lincoln needed their support. However, the skeptical appraisal of Lincoln’s gradual embrace of evangelical pieties and Christian abolitionism doesn’t stand up to what many close to Lincoln during his presidency observed. Orville Browning, the Republican governor of Illinois and close political ally to Lincoln; Mary Todd Lincoln (who had always been religiously devout); Joshua Speed, another friend and ally to Lincoln during the war; and Francis Carpenter, the presidential artist who briefly resided with the Lincoln’s in Washington, all observed a growing religious piety and transformation within Lincoln over the course of the war. Zeitz, quoting Browning’s wartime reflections, reminds readers that during the war, “[Lincoln] was reading the bible a good deal.”

This should not be surprising since the war transformed Protestantism in the United States, and here is another great highlight of Zeitz’s work—showing how the war also shaped a new identity for American Protestantism: black, white, mainline, and evangelical. Even before the outbreak of the Civil War, the crisis over slavery had fragmented many Protestant churches along seemingly geographic lines but those divisions were really over slavery. The biggest fragmentation was among the Baptists, where northern and southern Baptists split on the issue of slavery to form their own denominations—and we are still living with the aftershock of this division two centuries later. As the war drew on and death littered the fields of America, Protestant churches began evolving their views of heaven, hell, divine providence, and even the end times in dealing with the trauma of the worst war in American history. The hope to be reunited with deceased loved ones who died on distant battlefields and buried in mass graves led many Protestant ministers and their churches to reconceive heaven as a place of filial reunion under the compassion of a caring and loving God rather than a place of eternal worship. Heaven was now conceptualized as a place of reunion and comfort where loved ones would be seen again.

Furthermore, the war led to a reappraisal of the American experiment. Evangelical leaders throughout the northern states proclaimed the war as a judgement upon the nation for its sins, foremost slavery, and its failure to have a political society that combined the brotherly love preached in the Bible and the egalitarianism of the Declaration of Independence. Notably, Zeitz highlights how evangelicals saw the Declaration, not the Constitution, as America’s founding document and promise. The war was not only a judgement, though, it was also an opportunity for repentance and reform—the one chance to rid the nation of its original sin of slavery and create a more just and moral (Christian) society. The war did, in fact, offer the chance for a “new birth of freedom.” We who live today may not necessarily recognize the religious undertone of that rhetoric, but Zeitz reminds readers that “new birth” was religious language and something deeply familiar to evangelicals who emphasized a new birth in Christ who freed sinners.

Given the realities of the religious environment in America during the war, it is again unsurprising to learn Lincoln’s reliance on Scripture for comfort and understanding amid the bloodshed and carnage. Not only was he turning to the Bible for literary inspiration—as he had always done—but now he was leaning on it to find solace in the death of his son alongside the death of so many of America’s flowering youth and young men, and to make sense of this terrible trauma which was dragging on and on.

Lincoln’s emerging faith was not that of a cold, calculating, Machiavellian politician. Zeitz brilliantly reminds this to his readers, “Though Lincoln issued several proclamations of thanksgiving and penance during the war, by 1863 these documents conveyed a markedly biblical tone and providential message.” Additionally, “These public utterances signaled a sharp break with Lincoln’s earlier tendency to resort to ‘reason, cold, calculating, unimpassioned reason,’ in communicating with the political public, but in more private settings, the president had already begun to invoke spiritual language in his official deliberations.” Lincoln’s spiritual metamorphosis seemed to be earnest and heartfelt even if some of the technicalities of this change remain elusive.

If there is one thing that the evangelicalism of the 1800s still has in common with the evangelicalism of today, it is its emotional theology. Lincoln undeniably began to drink from the evangelical theology of emotion. Again, this should not be shocking. The grief of death on such a mass scale would cause emotional distress, as would the death of any son—let alone one as young as Willie. The evangelical piety that stressed emotional comfort rather than rationalistic dogmatic proclamation (as with the confessional churches), clearly spoke to Lincoln as it also did the nation at large. It’s important to remember that Lincoln was a human, like all other Americans suffering during the war. In that suffering, he turned to what could comfort him and comfort the nation—the evangelical theology of emotional comfort and closure that spoke to the heart and not the dictates of creeds and confessions. Lincoln’s speeches and proclamations reflect this embrace of the theology of emotional comfort amid grief. This attempt at comfort amid loss is also a forgotten part of the Gettysburg Address, “We here highly resolve that these dead shall not have died in vain—that this nation, under God, shall have a new birth of freedom—and that government of the people, by the people, for the people, shall not perish from the earth.”

Even though Lincoln’s God “remained, for him, a more abstract and unknowable force,” the president “grew more religious” as the war dragged on. And as the war dragged on, Lincoln’s famous open-door policy attracted more and more Evangelicals to visit. Evangelicalism, as the Civil War continued, increasingly became more abolitionist, more Republican, and more supportive of Lincoln’s war efforts. Evangelicals and Lincoln came closer together in unity in confronting slavery, supporting abolition, and seeking to find meaning and comfort in the ongoing bloodbath of the war. This relationship was, by all accounts, genuine as Zeitz shows. Lincoln relied on Evangelicals and Evangelicals supported Lincoln in the war to eradicate slavery, save the Union, and begin building a new nation conceived in liberty for all.

The drama and trauma of the Civil War changed Lincoln and the nation. Lincoln and America changed together, for the better. Lincoln not only began to “view himself as God’s ‘instrument’ on earth,” but also leaned on evangelical political support for prosecuting the war and abolishing slavery—becoming “the first president to understand and channel the spiritual and institutional power of evangelical churches.” Lincoln’s God is an excellent addition to all the scholarship written on Lincoln, America’s truly indispensable president, highlighting how black and white Americans conceived the war, changed their understanding of Christian theology, how our sixteenth president gradually drew nearer to Christianity even if that faith remained somewhat elusive and open-ended. Lincoln’s evangelical piety forged in the fire of the Civil War was social and moral in nature: the abolition of slavery, the brotherhood and dignity of man, emotional comfort to the grieving, and a providential understanding of history. Even if Lincoln remained undogmatic about the technicalities of evangelical theology, Zeitz isn’t wrong to call him “the nation’s first evangelical president.”