I’m sitting in the waiting area of Connecticut Sen. Joe Lieberman’s office. On the wall are photos of his years in the Senate. He’s smiling with telltale cheeriness in all the photos, save one in which he sits, brow furrowed, next to Gen. David Petraeus. That seems appropriate. With the exception of Sen. John McCain (R-Ariz.), there is no lawmaker who’s done more to support our military efforts against jihadist terror, often against a rising tide of public opposition. His effort to restore the “Scoop Jackson” wing of the Democratic Party has been largely a failure. A conservative wit once remarked to me, “He is the Scoop Jackson wing.”

Ironically, the TV in his office is turned to CNN, which is covering the speech of Palestinian leader Mahmoud Abbas at the U.N. General Assembly. He’s there to hawk his unilateral declaration of independence, a step that would violate decades of U.N. resolutions. So naturally, he’s met with rapturous applause by the delegates of Israel-hating countries — in other words, most of the audience. It reminds me of the bar scene in “Star Wars,” colorful characters oozing corruption and ill-intent.

Lieberman greets me with his usual enthusiasm. Despite the world’s travails and Israel’s multiple threats that are dominating the news and have occupied a great deal of his career, I am there to talk about his non-working life, or more specifically, his day of rest. His new book, “The Gift of Rest, Rediscovering the Beauty of the Sabbath,” is a guide to the sabbath, for Jews “Shabbat” (Hebrew) or Shabbos (Yiddish). As an Orthodox Jew, he has in a very public way had to navigate through a career that operates on a non-Jewish schedule and often features Friday night or Saturday events. He tells me, “Some of it is very theological, but I wanted it to be accessible. I was trying to make you feel like I was inviting you to follow me through the day.” While he considered arranging the material thematically, he eventually decided on a chronological order, beginning with Friday afternoon preparations and ending with Havdalah, the ceremony that marks the separation between Shabbat and the rest of the week.

Is the book related to his impending retirement next year? He says, ”I don’t have a good answer why” he is writing the book now. He’d been considering doing such a book for years and now, he says, “it felt like the right time.” Perhaps, since Shabbat is to a great extent about putting our professional lives to the side, he concedes there was some “subliminal” relationship to the coming end of more than 20 years in the U.S. Senate. He jokes that because he “wasn’t hustling for money” around the country to raise campaign funds he had the time to write the book.

The book is in some respects an “easy read.” It’s just over 200 pages, and it reads as if Lieberman is chatting with you. He explains religious practice, but also his childhood memories and secular rituals (bringing flowers home on Friday), all of which cast Shabbat is a special light. He said that the title of the book — “The Gift of Rest” — is taken from the Talmud. “What started out as a commandment I experience as a gift. It wasn’t always that way. As a kid I wished I had gone to ballgames and theme parks with my friends.”

But as an adult he’s come to look forward to it and enjoy all of its pleasures. He writes in the book. “For me, Sabbath observance is a gift because it is one of the deepest, purest pleasures in my life. It is a day of peace, rest and sensual pleasure. . . . [I]t engages the senses — sight, sound, taste, smell and touch — with beautiful setting, soaring melodies, wonderful food and wine and lots of love.” He tells me that voters and his colleagues “know what I don’t do — work — but they don’t know what I do” on Shabbat. He wants to dispel the notion that Shabbat is “a day of denial or seclusion. It does of course have serious moments.” But, he says with a grin, “By and by we have a great time.”

His book conveys that far from a passive exercise, Shabbat, and the preparations before it, are jammed with activity — special meals, synagogue services, time with friends, reading for pleasure, walks and time with family. He also raised some eyebrows in discussing that “one religious ‘responsibility’ given to every married Jew is to make love with their spouse on the Sabbath because this is meant to be a day on which we experience the fullness of life.” The book, stops at the “bedroom door,” but he does tell the reader, “Much of the staging of Friday night is conducive to romance: the passionate ‘Song of Songs’ is red, the wine, the candles, the set table, everyone dressed up and looking their best yet relaxed and unhurried. It’s a brilliantly conceived recipe for reunion.”

The book explains the structure of the services and the content of the traditional prayers, but it is also infused with Lieberman’s childhood memories — “my sense of expectation, the magic of lighting the candles, first by my mother and then by my wife.” Ritual rooted in memory is a powerful thing. He tells me that his oldest son, now in his 40s, still wants to receive the traditional blessing of the child that parents perform.

Not everyone will follow all the Shabbat rituals and requirements, he says. But in writing the book, “I was just hoping you’ll start.” To that end he provides a listing at the end of each chapter of easy steps and activities you can adopt. (Turn off the BlackBerry. Go outside. Eat dinner in your dining room, rather than the everyday kitchen.) The book is not only for Jews, and many of the non-liturgical elements can be applied to Christian Sabbath worship as well.

The book also explain the rules and choices concerning breaking of Shabbat and when Lieberman has chosen to depart from his gift of rest. That, however, is not the focus of the book. It is rather a loving guide and inspiration to enjoy a day separated from our ordinary demands. The psychological and theological insight is that by excluding workday cares for one day, you find that the rest of your days become richer and more fulfilling. Not a bad message, for an overscheduled society.

On Monday I will report on the rest of my interview with Lieberman when he talks about military spending, the debt, the Middle East and the presidential election.