During the past 11 days of heartache and anger, Erika Kirk has found herself returning, as if by gravitational pull, to a single moment. It is the recollection of how, on what turned out to be the last night of Charlie Kirk, her husband, he was too excited to sleep.

“His adrenal glands were just going off,” she recalled during an hour and a half interview on Thursday, eight days after Mr. Kirk, 31, one of the nation’s pre-eminent conservative influencers and the founder of the youth activist group Turning Point USA, was gunned down while debating students at Utah Valley University.

“He got up and I could hear him eating something in the kitchen. He’d been waiting all summer to begin touring.” The visits to college campuses, she said, “were like an Olympic event for him. He trained for them. He had whiteboard sessions for hours. Mock debates. He was just so excited.”

Mr. Kirk finally fell asleep sometime later, in another bed in the house. Ms. Kirk heard him slip out early the next morning. She texted “I love you” to him before his chartered plane took off for Provo, Utah. A staff member later told her that he had overheard Mr. Kirk proclaiming to the pilot as he disembarked, “Today’s going to be a great day.”

Ms. Kirk, 36, spoke in a composed voice while fighting through tears about a husband lionized on the right as an inspiration to young Republicans and pilloried on the left for his attacks on civil rights, feminism and Islam. She acknowledged her struggle to make sense of an unfathomable tragedy.

“I’m allowing myself to feel this so deeply,” she said, “without medication, without alcohol. The Lord is giving me discernment.”

She sat in workout clothes with her legs folded under her on a couch in a rented condominium in Scottsdale, Ariz. Her husband often used the condo as a way station between their home in a gated community outside Scottsdale and the Turning Point USA headquarters in east Phoenix.

Around her neck was the pendant of St. Michael that her husband was wearing when he was shot. The medics had ripped it from his body while attempting to stop the bleeding. A trace of blood remained in the crevice of the cross.

The bathroom floor of the condo was still littered with towels from her husband’s last shower there, a little more than a week ago. “To this day, I can’t go into my bedroom,” Ms. Kirk said. “I’m rotating where I sleep.”

Turning Point USA announced the day before the interview that Ms. Kirk would replace her husband as its chief executive. The organization’s spokesman, Andrew Kolvet, described her as its “beating heart, spiritual center and life force.”

But he said that no one could be expected to fill the shoes of Mr. Kirk, who had built Turning Point from scratch starting in 2012 into a sprawling conservative behemoth with $96 million in annual revenues. It was not immediately clear if Ms. Kirk would seek to continue her husband’s daily podcast or, for that matter, to joust with liberal students on college campuses.

Still, numerous Turning Point staffers said Ms. Kirk had the fortitude to be the group’s new leader. She has also received a vote of confidence from President Trump, who has called her twice since the shooting. The two have known each other since 2012, when Mr. Trump was running the Miss USA beauty pageants and she was Miss Arizona.

“Charlie was like a son to him,” Ms. Kirk said. “And when the president said, ‘Just let us know how we can support you,’ I told him, ‘My husband just loved conversing with you and using you as a sounding board for all sorts of things. Could we continue that?’ And he said, ‘Of course.’”

The president’s tone, she said, “was soft and embracing. I could tell he wanted to hug me.”

Others have responded in the same manner to Ms. Kirk, now left to care for a 3-year-old daughter and a 1-year-old son. That new life, Ms. Kirk said, “is actually the least traumatizing thing for me,” since she herself had been raised by her mother after their parents divorced when she was young.

Ms. Kirk provided the outside world with a glimpse of her resolve during an emotional 15-minute speech to a livestream audience, two days after her husband was murdered and hours after the 22-year-old man charged with his murder, Tyler Robinson, was taken into custody. Reading from notes that she had mostly compiled during the previous night when she was unable to sleep, Ms. Kirk vowed, “No one will ever forget my husband’s name, and I will make sure of it.”

She insisted on giving the speech live, rather than recording it ahead of time, she said, “because that’s what Charlie would do, for sure.”

‘I Want to See What They Did to My Husband’

On the evening before Mr. Kirk traveled to Utah, he and his wife met for dinner in the Phoenix area with a friend who was a faith leader. The purpose was to pray together over Mr. Kirk’s imminent tour of roughly 20 campuses. Both Ms. Kirk and the friend were worried.

Mr. Kirk, whose appearances on college campuses drew ardent support and fierce condemnation, had received numerous death threats over the past year and had been traveling with a security team for months. Over dinner, Ms. Kirk implored her husband to start wearing a bulletproof vest. When he demurred, the friend suggested that Mr. Kirk speak behind bulletproof glass.

“Not yet,” Mr. Kirk replied. He said he felt confident in his team, and that there would be additional security at the Utah event. But Ms. Kirk, like several of her husband’s subordinates, had occasionally heard him imply that his life could be cut short by violence. She found herself wondering if a part of him had already surrendered to such a prospect.

It had been Ms. Kirk’s plan to accompany her husband to Utah. But her mother would be undergoing medical treatment in the Phoenix area that same day. “Home needs you,” Mr. Kirk told her. They agreed that she would instead travel with him on the next leg of the tour, to Colorado State University.

Ms. Kirk was sitting in her mother’s hospital room at 11:23 a.m. local time in Phoenix when she saw the number of her husband’s longtime assistant, Michael McCoy, appear on her phone. In retrospect, she said she knew the words — “He’s been shot!” — before Mr. McCoy screamed them.

Mr. Robinson had texted his partner about Mr. Kirk after the shooting. “I’ve had enough of his hatred,” he wrote, according to court papers.

Mr. Kirk’s chartered plane traveled back to Scottsdale to ferry his wife to Provo. He was pronounced dead as she was airborne. “I’m looking at the clouds and the mountains,” Ms. Kirk recalled of those surreal hours. “It was such a gorgeous day, and I was thinking: This is exactly what he last saw.”

The sheriff met her in the hospital. He offered her the option of seeing the body but, she said, advised against it. The bullet, he explained, had ravaged Mr. Kirk’s neck.

“With all due respect,” Ms. Kirk remembered saying, “I want to see what they did to my husband.”

She was braced for the worst, but what she saw surprised her. “His eyes were semi-open,” Ms. Kirk said. “And he had this knowing, Mona Lisa-like half-smile. Like he’d died happy. Like Jesus rescued him. The bullet came, he blinked, and he was in heaven.”

She had not been able to kiss him goodbye when he left the house earlier that morning. She did so then.

Dating a Miss Arizona

During an episode of “The Charlie Kirk Show” on radio and streaming earlier this year, Ms. Kirk joined her husband and read out some questions the audience had submitted. The first questioner wanted to know which of the two was more conservative.

“Erika,” said Mr. Kirk. “By far. Not even close. I am a moderate compared to Erika.” His wife concurred.

In the interview, Ms. Kirk described their bond as one modeled after the fifth chapter in the Bible’s Book of Ephesians, in which the wife submits to the husband, who in turn, according to the Bible, protects and cherishes the wife, “just as Christ also loved the Church and gave himself for her.”

Mr. Kirk first met the former Miss Arizona at a Turning Point event in 2018. He later flew to New York, where she then worked as an entrepreneur of Christian-themed clothing, ostensibly to interview her for a job.

As they met over burgers in Manhattan, it quickly became apparent that the two had chosen different paths while remaining not so far apart. Both were born in the Midwest, Mr. Kirk in Illinois, Ms. Kirk in Ohio. Both had been basketball stars in high school. He had never attended college but was a voracious reader. She had received a bachelor’s degree at Arizona State University and a master’s in legal studies at Liberty University.

And while Mr. Kirk was building a conservative powerhouse in Phoenix, Ms. Kirk, who had spent her adolescence in nearby Scottsdale, had chosen to live in Manhattan.

Once he had confessed that he wanted to date her rather than hire her, and she recovered from the shock, “he engulfed me into his world,” Ms. Kirk said. “I made that choice. It’s so hard to articulate the beauty of an Ephesians 5 marriage when you actually have a man that’s worth following, to have a true example of a leader to look up to. And I had that in Charlie.”

In other words, Ms. Kirk said, their conservative Christian union felt organic rather than imposed. They watched sports and played one-on-one basketball together. He never drank and she seldom did. They preferred each other’s company, she said, over hanging out with others.

Once they married in May of 2021, Ms. Kirk said she tolerated his dude-ish clutter, seeing the clothes on the floor as the detritus of an intensely focused young man. He avidly wrote in journals, which she never read while he was alive. Only after he died, she said, did she look at a few of his pages and marvel at “the intricate inner workings of his brain and his heart.”

Still, nothing that she read in the journals was new to her. “I was his vault,” she said. Despite his fame in conservative circles and the debates he relished with college students, she described him as an introvert. In turn, Mr. Kirk sought to fulfill his own Ephesian covenant in cherishing and protecting his wife. Every Saturday he would leave a handwritten note for Ms. Kirk, always asking some version of: “How can I best serve you?”

She never answered.

“I’m not saying he was perfect, by any means,” Ms. Kirk said. “But I knew my expectations and role, and he knew his. I wasn’t going to be the nagging wife who he wouldn’t want to come home to. I wanted to create a sacred landing space for him. And I think that’s why he was always eager to come home.”

Blood on a Ledger

As Ms. Kirk prepares for Mr. Kirk’s funeral on Sunday, when Mr. Trump and nearly every other major conservative figure is expected to sanctify her husband, she has her own mortal preoccupations.

Beyond the grief, she said, sometimes she is able “to see the Bible in such technicolor. To be so serene in saying, ‘Thy will be done. I surrender to it.’ Do I like it? No. That was the love of my life, my soul mate, my best friend. But God’s plan is always greater than ours.”

Like other Christians at Turning Point, she said she sees a divine logic to Mr. Kirk’s death: a young prophet whose fleeting life has achieved lasting resonance after his martyrdom. While others seek out conspiracies beyond the death of Mr. Kirk at the hands of a lone gunman, Ms. Kirk is not among them.

In her view, a young but towering spiritual voice was silenced by a young lost soul. “I’m a strong believer that this was God’s plan,” she said. “And it’s so clear-cut. It couldn’t be more Charlie.”

She added, “I’ve had so many people ask, ‘Do you feel anger toward this man? Like, do you want to seek the death penalty?’ I’ll be honest. I told our lawyer, I want the government to decide this. I do not want that man’s blood on my ledger. Because when I get to heaven, and Jesus is like: ‘Uh, eye for an eye? Is that how we do it?’ And that keeps me from being in heaven, from being with Charlie?”