Updated

For the second time in a week, Arizona Sen. John McCain is telling critics to get a life for complaining about his using the serious subject of war in what are supposed to be humorous remarks.

"We really have kind of lost our sense of humor and sense of balance," McCain told FOX News on Thursday.

A day earlier, McCain was criticized by Rep. John Murtha, D-Pa., an opponent of the war in Iraq and a Vietnam veteran — like McCain — for McCain's appearance Tuesday night on "The Daily Show With Jon Stewart."

Stewart, who has had McCain on the show more times than any other guest, asked the 2008 Republican presidential candidate whether he wanted to start their conversation with McCain's joke to a group of veterans about bombing Iran or his recent trip to Iraq in which he walked through a Baghdad market that he later described as safe despite wearing a flak jacket at the time.

Click here to watch McCain sing.

"Let's see. Which one have I seen most on your show?" McCain asked Stewart. "I think maybe shopping in Baghdad. I had something really picked out for you, too."

"Did you really?" Stewart asked.

"Yes, it's a nice little IED to put onto your desk," McCain joked.

The two then went into a semi-serious discussion about the Baghdad market, with Stewart pointing to a comment by GOP Rep. Mike Pence, who joined McCain, comparing the Baghdad market to any farmers' market in Indiana. McCain said Pence meant both places are willing to accept plastic for payment.

McCain's humor didn't sit well with Murtha. Speaking on the House floor during the debate on including a timetable to the war supplemental spending bill, the head of the House Defense Appropriations Subcommittee slammed his fist down onto the table and yelled out that a "presidential candidate" owes an apology to military members, including all those killed and wounded while serving in Iraq.

“These kids are getting blown apart. It’s outrageous,” Murtha said of McCain's remarks. He later called McCain’s remarks “disturbing.”

Asked about Murtha's response, McCain wondered to whom he owes an apology.

"Apologize to who, to Jon Stewart? Because I was joking around on a comedy show. I can't respond to that kind of hysteria. I am going to continue to use humor particularly when I am on a comedy show. If Congressman Murtha or anybody can't adjust to that, then lighten up and get a life," he said.

He also brushed off complaints of the previous week in which McCain answered a question from an audience member at the VFW in Murrells Inlet, S.C., by going into a paraphrased chorus of the Beach Boys song "Barbara Ann."

“Bomb-bomb-bomb, bomb-bomb Iran,” McCain said to a laughing audience.

Click here to watch McCain sing.

Asked about the criticism that accompanied that joke, McCain said he is going to continue to use his quirky brand of humor.

"It was very important to me in many difficult times in my life and I will continue to do it and we are going to continue to have fun," said McCain, who spent 5-1/2 years as a POW in North Vietnam.

"And if that's somehow harmful to my presidency then that is certainly the penalty I will pay. But I think most Americans enjoy humor from time to time and I am confident that they will enjoy my feeble attempts even though it gets a bit corny at times."