Christmas comes but once a year, the old saying goes. It's a federal holiday as well as a religious observance, so it's understandable that any president of the United States, regardless of faith, would take the day off. At the same time, most every POTUS has been a Christian of one stripe or another (questions exist about Jefferson and Lincoln, but that's for another time).

President Barack Obama professes Christian faith as well, something noted here just the other day.

But personal faith and public (or semi-public) practice are often two different things. Ronald Reagan's non-attendance at church (not to mention his wife's reported dabblings in astrology) drew barbs from some political opponents and pundits. George W. Bush often hosted worship services at Camp David but was not a frequent churchgoer when in Washington. (That said, Bush averaged 15 visits to churches each year, versus 3.6 per annum for Obama.)

The New York Timescaught this, and jumps in on what the president did -- and didn't -- do during his current, Christmastide sojourn in Hawaii:

HONOLULU — President Obama celebrated a low-key Christmas in Hawaii this year. He sang carols, opened presents with his family, and visited a nearby military base to wish the troops “Mele Kalikimaka” — the Hawaiian phrase meaning “Merry Christmas.”

But the one thing the president and his family did not do — something they have rarely done since he entered the White House — was attend Christmas church services.

“He has not gone to church, hardly at all, as president,” said Gary Scott Smith, the author of “Faith and the Presidency: From George Washington to George W. Bush,” adding that it is “very unusual for a president not to attend” Christmas services.

Historically, watching the nation’s first family head to church dressed in their Sunday best, especially around the holiday season, was something of a ritual. Yet Mr. Obama’s faith is a more complicated, more private, and perhaps — religious and presidential historians say — a more inclusive affair.

One of the big changes from, say, the Truman and Eisenhower years to today is the security. Following the assassination of John F. Kennedy and attempts on the lives of Gerald R. Ford and Ronald Reagan, the Secret Service is naturally skittish about having the POTUS in situations where it's tough to control security. At the same time -- and this was reportedly Reagan's explanation for skipping church attendance -- having a security detail disrupt the setting and flow of a worship service isn't kind to the congregation involved.

This said, the Times, as did its Los Angeles namesake a few days before, concentrates on contrasting Obama exclusively with Republican presidents, living and dead, and not Democratic ones. There's just no mention of FDR, Truman, Kennedy, Johnson, Carter (who taught Sunday school regularly) or Clinton. Zero, zip, nada.

As to getting to a church on time, plans can be made, exceptions taken. Obama does occasionally cross Lafayette Park to attend worship at St. John's Episcopal Church, also known as the "Church of the Presidents." But St. John's, which has hosted every U.S. president since James Madison, is familiar with the Secret Service's procedures and could presumably accommodate the Obamas and their security detail without too much hassle. Still, the NYTimes notes Obama's infrequency:

Mr. Obama has gone to church 18 times during his nearly five years in the White House, according to Mark Knoller of CBS News, an unofficial White House historian, while his predecessor, Mr. Bush, attended 120 times during his eight years in office.

But those numbers do not reflect the depth of Mr. Obama’s faith, said Joshua DuBois, the former head of the White House Office of Faith-Based and Neighborhood Partnerships. “President Obama is a committed Christian,” said Mr. DuBois, who sends the president a daily devotional by email, and is the author of “The President’s Devotional.”

There's a lot of discussion of various "inclusive" observances Obama has had at the White House. Although Jewish staffers in the Clinton administration had Passover seders at the White House starting in 1999, Obama was the first president to sit in on one. And while George W. Bush celebrated the first modern Ramadan dinner at the White House in 2001, his successor has continued the practice.

But where does this leave Christianity and that religion's annual observance? Muddled, it seems:

Yet the public rituals of religion have proved tricky for Mr. Obama. When he arrived in Washington after his election in 2008, many of the city’s churches began furiously vying to have him and his family join their congregation. As president, he has attended services at several of the city’s African-American churches, as well as St. John’s Episcopal Church, which is across the street from the White House. But he ultimately opted against choosing a spiritual home in the nation’s capital.

“I think part of the reason he’s been wary of affiliating with a church in Washington is that he got so burned by the Jeremiah Wright situation, and he’s kind of backed away from that,” Mr. Balmer said.

The public has long cared about the religion of its president. President Dwight D. Eisenhower, for example, was not a regular churchgoer before he entered office. After he was elected, at the urging of the Rev. Billy Graham, he joined the Presbyterian Church, and was baptized, becoming a diligent member of the faith.

Then again, Obama may be doing what a lot of other, non-presidential Americans do on Sundays, which is making a choice about their "free time" and its use:

Mr. Balmer put it more bluntly: “If the calculus is, ‘Do I spend two hours going to church Sunday morning or do I get to watch college basketball Sunday afternoon?’ If he had to choose between the two, and knowing Obama, he’d probably choose college basketball.”

He added, with a laugh, “And that’s a calculation many Americans make on a weekly basis.”

Whatever the reasoning for Obama's actions, the lack of any mention of another Democratic president in the mix is puzzling.  I'm also not sure why it might seem the current occupant of the Oval Office should be contrasted with Eisenhower, at least in terms of their faith practices. And if Obama has decided in favor of college hoops over clerical collars, that also, I believe, deserves more substantiation than the comments of a religion scholar.

Also, there is no mention of the lingering D.C. tensions over the fact that Obama never joined a historically black church in the city, nor does he attend one regluarly.