David French and Nancy French recently published pieces questioning the integrity and “prophetic witness” of evangelical leaders for their support for Donald Trump. Both articles mainly concern hypocrisy, so I’ll let the accused defend themselves. I have no commitment to Franklin Graham’s words and deeds any more than I do the Frenches’. But their argument, if it has any universal application at all, must go beyond a few people’s alleged hypocrisy. Why shouldn’t I vote for or support Donald Trump?
What is striking about NeverTrump evangelical arguments against evangelical support for Trump is how thin the actual reasoning is. It typically amounts to “don’t be a hypocrite,” “don’t pursue power over principle,” “don’t support an immoral man,” and “don’t compromise your Christian witness,” followed by a list of all the evils and moral errors of Trump. Such argumentation reflects the sorry state of evangelical political theology. I’ve encountered no attempt by a NeverTrump evangelical to precisely and systematically present what I call a “theory of voting,” something akin to ethical theory. Voting theory refers to the principles and factors that a voter ought to use when making a voting decisions in political elections.
As I’ve shown, the construction of a theory of voting is actually complicated and difficult, especially for those who recognize different layers and types of sin (for not all sins seem relevant to our voting decisions). Voting is certainly an ethical choice, but only to the extent that ethics informs politics, for voting is ultimately a political choice. Strictly speaking, politics and ethics are separate subjects such that one might, without contradiction, affirm consequentialist thinking in politics while reject it in ethics. Hence, one might say (as I have) that good politics produces ethical outcomes. That is, ethics and politics are intertwined, but they follow different principles. Since voting is principally a political choice, it follows a consequentialist principle.
For this reason, one’s voting theory cannot be a set of disparate moral maxims or mantras, tossed ad hoc upon one’s opponents when useful, as we see in trendy evangelical thinking. Most importantly, the theory must make distinctions — something that NeverTrump evangelicals rarely offer in their condemnations of Trump and his evangelical supporters.
David French, however, tells us that the principles of voting and support are “not hard to articulate.” This is presumably how his wife Nancy French could without hesitation endorse Mitt Romney, a Mormon, back in 2012: their disagreement is merely “theological.” Supporting Trump, who is immoral, is obviously out of the question, however. Evangelicals should not spoil their moral witness by supporting an “immoral” man.
But, given the Frenches’ theological and political commitments (they are both conservative Presbyterians), one can produce the following set of syllogisms:
(1) Anyone who fails to give God his due in worship has committed the worst sin possible (per the classical Protestant tradition). 
(2) Mitt Romney has failed to give God his due in worship (as a Mormon).
Therefore, (3) Mitt Romney has committed the worst sin possible.
(4) Anyone who commits the worst sin possible is an immoral man.
(3) Mitt Romney committed the worst sin possible.
Therefore, (5) Mitt Romney is an immoral man.
(6) No Christian is permitted to vote for or support an immoral man.
(5) Mitt Romney is an immoral man.
Therefore, (7) No Christian is permitted to vote for Mitt Romney.
(8) Any evangelical who votes for or supports an immortal man undermines his Christian moral witness.
Given (5), (9) David and Nancy French voted for an immoral man (Mitt Romney).
Therefore, (10) David and Nancy French undermined their Christian moral witness.
Now, this set of valid syllogisms is not meant to prove that the Frenches have compromised their moral witness. They would no doubt want to distinguish different types of immoralities and thereby make the term “immoral man” an equivocation. But on what coherent and workable principle can we distinguish the immorality of false worship and other types of immorality? If supporting a candidate endorses his immorality, then why doesn’t voting endorse all the candidate’s immorality, including errors concerning worship (viz. First-Table precepts)? What is the principle of distinction that makes some sins endorsable in voting and others not?
To my knowledge, no NeverTrump evangelical has offered any such distinction. David French, for example, tells us the following in a May 2018 article:
We are not told, however, to compromise our moral convictions for the sake of earthly relief, no matter how dire the crisis. We are not told to rationalize and justify sinful actions to preserve political influence or a popular audience. We are not told that the ends of good policies justify silence in the face of sin….I’m sorry, but you cannot compartmentalize this behavior, declare that it’s “just politics”…. It’s sin, and it’s sin that is collapsing the Evangelical moral witness.
French provides no principle to distinguish the array of Christian “moral convictions”. Indeed, his argument in its form is just as effective for any politician’s failure to worship God or recognize the Sabbath. Sill, the Frenches are willing to remain silent before Romney’s theological sin. But why? What’s the distinguishing principle? Why do violations of the 7th Commandment matter, but not those of the 1st or 2nd? Why does support for those who fail to properly worship the Christian God not compromise Christian moral witness? French says that we must “not compromise our true purpose.” What is man’s true purpose but to glorify God in worship?
One might say that the principle to distinguish immoralities is this: only sin that has earthly and civil consequences is relevant. This is a good start (though it must come with a reason to believe it), but now we’re dealing with consequences; and in consequentialist determinations we judge the rightness or wrongness of choices by the preponderance of good or bad that results. Given Trump’s policy choices and achievements, the rightness or wrongness of supporting him is not as morally obvious as the Frenches and the NeverTrump evangelicals make it seem. This might explain their unwillingness to offer any precise principle of voting: any precision makes their moral denunciations less plausible and principled. It explains at least why NeverTrump evangelical arguments have been so bad.
Despite the moralistic language and support from liberal papers like the Washington Post, evangelical NeverTrump moral denunciations have no apparent theoretical justification. Their own mess of mantras leads either to practical absurdities (e.g., can’t vote for Mitt) or simplistic moral denunciations. Since these denunciations are theoretically groundless, they can be dismissed and ignored. Until NeverTrump evangelicals can produce some coherent and workable basis for their denunciations, they (not their Trump-supporting opponents) seem to be the ones lacking moral witness.
 “The chief part of righteousness and holiness consists in the true worship of God.” John Calvin (on Micah 4:2). “As the name of God is more excellent than any thing in the whole world, so the worship of him ought to be regarded as of more importance than all those duties by which we prove our love towards men.” Calvin (on Micah 6:8)
 Conservative evangelicals typically consider Mormonism to be heretical.
 This seems to follow from these words of David French: “A Christian’s primary purpose is not to defend his own religious liberty. It’s not even to fight abortion — as vital as that task is. His basic task on this Earth isn’t protecting Christian education or preserving the freedom of Christian artists. Each of those things is important. Each of those things is necessary. But their defense cannot and must not compromise our true purpose.”
 To be clear, I see no problem in principle with voting for a Mormon. But I can say this because it follows from my theory of voting.