As messed up as things are on Capitol Hill these days, you can’t help but wonder: Does Congress have a prayer?

Actually, it does. Two prayers, in fact: one in the House and one in the Senate, delivered every day by their respective chaplains. It is not my place to say whether those prayers do any good. Rather, it is my place to say that a new book explores a very narrow slice of the historic practice.

The book is called “When Rabbis Bless Congress: The Great American Story of Jewish Prayers on Capitol Hill” (Cherry Orchard Books).

“You can’t get any more niche than this sliver of congressional and Jewish history,” author Howard Mortman told me.

Mortman is the perfect person for the job. Since 2009, the McLean, Va., resident has worked at C-SPAN, where he is communications director. He watches a lot of C-SPAN.

“I’ve always been intrigued at the novelty of the whole concept of opening each session with a prayer, because it looks like nothing else Congress does all day,” said Mortman, 53. “They pray before they even have the Pledge of Allegience. It’s a tradition that goes back to the beginning.”

That would be the first session of the Continental Congress in 1774, which opened with a prayer from the Rev. Jacob Duché, of Christ Church in Philadelphia.

No rabbi has ever been an official chaplain, a paid job that comes with an office and staff. But, by Mortman’s count, 441 rabbis have come in off the bench.

“On days that the chaplains aren’t performing their duties, they have guest chaplains, like the guest host when Johnny Carson wasn’t behind the desk,” Mortman said. “That’s where my story begins.”

It begins with Philadelphia’s Morris Raphall, the first rabbi to offer a congressional blessing. That was on Feb. 1, 1860. At the time, the House of Representatives was dickering over picking a speaker. According to the New York Times, Raphall “implored divine blessing to direct the House in the election of a speaker who may preside without favor and fear, and that members might speak and act for the glory and happiness of their common country. The prayer was listened to with marked attention.”

Some of the attention was directed at what was described as Raphall’s “costume.” Many of those present had never seen a yarmulke and prayer shawl.

The Chicago Tribune noted that a rabbi saying a prayer in Congress made some people — i.e., Christians — uncomfortable. But the paper asserted: “Let timid religionists learn that freedom is more than safe for truth and right. It is the very atmosphere in which they live and flourish.”

Atheists and others may squirm at this mingling of church and state, but it’s in the rules, Mortman notes. C-SPAN tries to play things down the middle. Mortman does the same.

To research the book, he scoured congressional records, the Library of Congress and other sources.

“I went through every prayer to try to figure out if this person was a rabbi or if a synagogue was mentioned,” he said.

It got easier after C-SPAN came on the scene in 1979. Mortman scrutinized hours of archival footage. That’s how he knows that of the 218 rabbis who delivered prayers in the “modern TV era,” 180 — 83 percent — wore yarmulkes.

Just one wore a prayer shawl: Mark Getman of Temple Emanu-El of Canarsie, in Brooklyn.

Wrote Mortman: “Getman has played a rabbi in ‘The Marvelous Mrs. Maisel.’ That makes Getman the first rabbi to appear on both C-SPAN and Amazon Prime Video.”

New York state has provided the most guest chaplains: 136 rabbis delivering 184 prayers. (Some have done it more than once.) D.C. is second in the number of prayers — 58 — but fifth in the number of rabbis: 22, coming after New York, Pennsylvania (38 rabbis), New Jersey (32) and Maryland (29).

Mortman’s 336-page book is packed with such rabbinical minutiae.

“It’s the Sabermetrics of rabbi guest chaplains,” he said.

Congressional chaplains are instructed to keep politics out of their prayers. Still, by their very history, some rabbis deliver a powerful message.

Rabbi Isaac Neuman, a survivor of Auschwitz, twice served as a guest chaplain. On April 11, 1983, he prayed: “May our country hold true to its traditions and remain a refuge for the homeless and oppressed, as it has been for us and for all our forefathers.”

Like the tree in the empty forest, there’s the question of who actually hears the prayers. The House and Senate chambers aren’t exactly packed first thing in the morning.

“That’s where being able to pray in front of a national TV audience comes into play,” Mortman said. Guest chaplains welcome the opportunity to address cable TV viewers.

Besides, maybe God is listening.

Twitter: @johnkelly

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