As the presidential primaries draw near, the nation is again focused on the candidates and their faith. During a recent Republican debate, a citizen viewer asked the candidates: "How you answer this question will tell us everything we need to know about you. Do you believe every word of [the Bible]?"

Some opinion writers immediately balked, claiming that such questions are harmful because faith has no place in the public square. Pundits on Sunday morning talk shows have cried "theocracy" over the very idea of religious arguments in political discussions. And observers on both sides of the aisle have warned that questions about candidates' religious beliefs violate the Constitution.

All of these accusations are misguided.

It's certainly constitutional for voters to ask candidates about their religious beliefs. People are free to vote for a candidate based on whatever grounds they choose. What's prohibited is using religion as a legal qualification for serving in office.

The prohibition on a religious test for office in Article VI of the Constitution places limits not on voters but on the federal government. The fact that Protestants, Catholics and a Mormon are in the race is proof that Article VI is alive and well.

Neither do questions about religion violate the so-called "separation of church and state." The First Amendment addresses the relationship between two institutional authorities, not the kinds of arguments that go into making political decisions.

The freedom Americans enjoy is the freedom to bring whatever arguments they like into political debates. James Madison envisioned a lively public square filled with arguments from all sorts of viewpoints; the Constitution he helped to author separates the authority of the church from that of the state, not religion from politics.

So questions about the Bible and other similar questions asked of candidates, such as frequency of prayer and church attendance, are constitutionally permissible.

But these are not the most critical issues pertaining to faith's role in this election, nor the most helpful in selecting a president. Wouldn't it be more fruitful to hear presidential hopefuls address how their faith would directly influence the particular challenges and responsibilities of the office?

The president has specific responsibilities identified by the Constitution. The office requires a certain level of knowledge, political instinct, competency and skill - including good communication and grasp of global economic and geo-political realities - to exercise those responsibilities well.

The premise of the recent debate question ("How you answer this question will tell us everything …") does not adequately account for these kinds of considerations. Nor does it account for the fact that people who claim the same approach to the Bible often disagree on their approach to politics, and that people with similar politics often disagree about religious doctrine.

The candidates' adherence to the Bible - and to their particular faith traditions - may say a lot about who they are, but it doesn't say "everything" about how effective they would be as president.

The serious role that religion exercises in public life calls for an open and honest discussion about faith in this campaign, and America would benefit from a more robust dialogue about the influence of religion in the Oval Office. But all of us - candidates, citizens and media - can do a better job of focusing on those aspects of religion that are most relevant to the responsibilities of the president. To paraphrase one writer, "All questions are permissible, but not all questions are helpful."

Ryan Messmore is the William E. Simon fellow in Religion and a Free Society at The Heritage Foundation (heritage.org).