Fea pointed out that many of the Founding Fathers were so wary of mixing faith and politics that the state constitutions they wrote barred ministers from holding public office.

Revolutionary War-era constitutions in North Carolina, New York, Georgia, South Carolina, Delaware, Tennessee, Maryland and Kentucky banned members of the clergy from running for office, says Fea.

North Carolina's 1776 Constitution says "that no clergyman, or preacher of the gospel of any denomination, shall be capable of being a member of either the Senate, House of Commons, or Council of State, while he continues in the exercise of the pastoral function."

The New York Constitution of 1777 is similar. It states, "And whereas the ministers of the gospels are, by their profession, dedicated to the service of God and the care of souls, and ought not to be diverted from the great duties of their function; therefore, no minister of the gospel, or priest of any denomination whatsoever, shall, at any time hereafter, under any pretense of description whatever, be eligible to, or capable of holding, any civil or military office or place within this State."

In his column, Fea criticizes David Lane, a Religious Right activist who is urging fundamentalist Christian pastors to run for office in the hopes of sparking a revival and making America a "Christian nation."

Observes Fea, "The Founding Fathers understood something about the role of clergy in American society that Lane and his Christian nationalist friends do not. Those who care for the soul have a `great' spiritual duty that should never be compromised or tarnished by politics. This is why they thought that the `separation of church and state' was important."

Fea doesn't mention it in his column, but Thomas Jefferson shared these concerns. In March of 1815, Jefferson responded to a letter he had received from Peter Hercules Wendover, a member of the U.S. House of Representatives. Wendover had sent Jefferson a series of sermons published by a pastor named Alexander McLeod about the recently concluded War of 1812. Jefferson agreed with McLeod's support for the war but took issue with the religious leader's decision to base so many sermons on it.

Jefferson wrote a long reply to Wendover dated March 13, 1815, but decided against sending it due to "mr Wendover's character & calling being entirely unknown." But Jefferson did save the letter, and it ended up among his papers. Speaking of McLeod, he observed, "On one question only I differ from him, and it is that which constitutes the subject of his first discourse, the right of discussing public affairs in the pulpit."

Preachers, Jefferson opined, should stick to what they know best: religion.

"[I] suppose there is not an instance of a single congregation which has employed their preacher for the mixed purposes of lecturing them from the pulpit in chemistry, in medicine, in law, in the science and principles of government, or in anything but religion exclusively," Jefferson wrote. "Whenever, therefore, preachers, instead of a lesson in religion, put them off with a discourse on the Copernican system, on chemical affinities, on the construction of government, or the characters or conduct of those administering it, it is a breach of contract, depriving their audience of the kind of service for which they are salaried, and giving them, instead of it, what they did not want, or, if wanted, would rather seek from better sources in that particular art or science."

Few people these days would argue that clergy should be denied the right to hold public office. Indeed, the U.S. Supreme Court in a 1978 case called McDaniel v. Paty declared Tennessee's ban on clergy running for office unconstitutional. 

But, as Fea's column notes, the old prohibition shines an interesting light into the mindset of the Founders. Many were definitely concerned about the corrupting influences an injudicious mixture of religion and politics imposed on both church and state.

Pastors today have the right to run for office just like everyone else - but they have no right to use the resources of their tax-exempt houses of worship to get themselves or any other candidate elected.

Trump and the right-wing evangelicals he is so aggressively courting would do well to bear that in mind.