(RNS) — Earlier this month, Florida Governor Ron DeSantis — viewed as a leading candidate for the 2024 GOP presidential nomination — received several standing ovations during his speech to the Faith and Freedom Coalition’s “Road to Majority” conference. He told the audience that “you got to put on the full armor of God” to “take a stand against the left’s schemes,” for “you will face flaming arrows but take up the shield of faith and fight on.”

This was a reference to a passage in the New Testament in which the Apostle Paul implored the Ephesians to:

“Put on the full armor of God, so that you can take your stand against the devil’s schemes.  For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms. Therefore, put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand. … (T)ake up the shield of faith, with which you can extinguish all the flaming arrows of the evil one.”

The dubious interpretive gymnastics required to apply Paul’s spiritual admonition to today’s hyperpartisan political landscape is just the latest example of Republican politicians aggressively merging their political and Christian identities. This isn’t particularly new: America’s politicians have always exploited our faith for votes. What’s different is that the tone of the political discourse has shifted as the religious landscape has changed in some pretty significant ways. 

The first change to keep in mind is that American Christianity is declining. In 2019, 65% of American adults described themselves as Christians, down 12 percentage points over the previous decade. With fewer Christians to offend and more non-Christians in the marketplace, media providers, corporations and universities are staking out positions on “culture war” issues that are in tension with traditional Christian beliefs.

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This phenomenon contributes to a perception among many American Christians that they are a persecuted minority surrounded by an increasingly hostile culture. Most white evangelicals today believe that Christians are more likely to face discrimination in the United States than Muslims. If Christians believe they face an existential threat, they will tend to support candidates whose rhetoric matches the gravity of the moment.  

The second change relates to the shift in party coalitions. Today, according to Pew Research, about half of Democratic voters identify as Christian, down from 73% as recently as 2008. The percentage of Democratic voters who are religiously unaffiliated has doubled during that time, from 18% to 38%. The change among Republicans has been more modest: Christians are 79% of Republican voters, down from 87% in 2008. Only 15% of Republican voters are religiously unaffiliated, up from 9% in 2008. 

This shift means that Republican politicians have an incentive to underscore the religious beliefs that most Republican voters hold in common and that many Democratic voters do not. Ezra Klein, in his 2020 book “Why We’re Polarized,” explains that group conflict today is not primarily motivated “by zero-sum collisions over resources or power,” but by the psychological desire to increase difference between the in group and the out group.

The result, according to University of Maryland professor Lilliana Mason in her 2018 book “Uncivil Agreement,” is our current predicament in which “partisan identities fall into alignment with other social identities, stoking our intolerance of each other to levels that are unsupported by our degrees of political disagreement.”

So, it may be in the short-term self-interest of Gov. DeSantis and other GOP presidential prospects to describe policy disagreements with language traditionally reserved for spiritual battles against demonic forces. But that does not mean that such rhetoric is anything but toxic, for both democracy and the public witness of Christians.

Besides portraying the Gospel itself as a partisan proposition, this language ratchets up the perceived stakes of our debates: our political opponents are not merely separated by ideology; they are enemies engaged in spiritual warfare. 

Further, such rhetoric quickly leads to a spirit of self-righteousness. If those who reject our political views are demonic — as Eric Metaxas and Franklin Graham suggested in a 2020 interview regarding opposition to President Trump, for example — then of course we enjoy the satisfaction of knowing that God is on our side. If we refuse to recognize the possibility that our political tribe is just as capable of evil as the other side is, we are denying the reality of sin.

That’s a theological problem, but it’s also a political one. Self-righteousness obscures the mutual fallibility on which the give-and-take of democracy depends. If our tribe is on God’s side and our opponents are on Satan’s, why would we ever consider compromise?

Pushing back against this rhetoric does not require a retreat to some sort of imagined secular space — the resources for resistance are available within Christianity itself.

Christians have long used religious language to advocate for particular policies, and there is nothing wrong with doing so provided that the religious language is an entry point, not the entirety of the argument.

The rule of law requires that the lawgiver offer reasons that are rationally accessible, even if not agreeable, to all. On both sides of the political spectrum, the most effective advocates convey the public relevance of Christian values in terms that are wide open to disagreement.  

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In his 1984 State of the Union address, President Reagan explained: “We must be cautious in claiming that God is on our side, but I think it’s all right to keep asking if we’re on his side.” Though the demographics of the American electorate have changed over the ensuing decades, the underlying principle has not: When we bring our faith into politics, a little humility goes a long way.

(Robert K. Vischer is dean of the University of St. Thomas School of Law in Minneapolis. The views expressed are his own. The views expressed in this commentary do not necessarily reflect those of Religion News Service.)