Jimmy Carter brought up death — specifically, his own — at what turned out to be the last Sunday school class he would teach at Maranatha Baptist Church. It was November 2019. He’d recently fallen and fractured his pelvis, a setback that followed a string of illnesses and injuries that reminded everyone around him — and himself, it seems — that despite his mental acuity and physical vigor, he was 95 and would not live forever.

Mr. Carter’s death on Sunday at 100, has spurred an examination of a sprawling legacy: the successes and failures of his presidency; his work to eradicate diseases and bolster free and fair elections; his involvement with nonprofits like Habitat for Humanity.

Here is something else he left behind: In a culture where death as a subject is often taboo and engulfed in an aura of fear, he amassed over the years — across writing, public comments and Sunday school lessons — a compilation of observations that amounted to a candid, cleareyed, evolving exploration of the end.

He wrote about death in books — and he wrote more books than any other American president. He discussed it in speeches and in correspondence with friends.

Those observations were a product of his Christian faith. His perspective also grew out of experience, a fluency with death that came from seeing many of his closest family members, including all of his younger siblings, die before him.

His views were also shaped by his own advancing age. He described the sense of the inevitable looming over him and the health challenges that had piled up, including cancer that had spread to his brain.

At Sunday school that morning in 2019, he said that he did not think he would survive for long after his cancer diagnosis. “I assumed, naturally, I was going to die very quickly,” he told the packed church. He lived nine more years.

Mr. Carter recalled the worries he had as a young person, stirred by learning in church about Jesus Christ’s crucifixion and resurrection and by the pastor’s sermons about how “all believers,” as he put it, “would someday enjoy a similar resurrection.”

“As I grew older,” Mr. Carter wrote, “I began to wonder whether this could be true.”

He was concerned as a boy that even an iota of doubt could lead him to a different fate, relegating him to an eternity separated from his family, particularly his parents. “These two people were the core of my existence,” he wrote, “and I couldn’t bear the idea that I would not be with them forever.”

As he matured, Mr. Carter’s faith firmed and came to define his approach to life — and death.

He considered himself a born-again Christian. In a 2012 interview with an influential evangelical theologian, Mr. Carter said his aim had been to “pattern my life and my own fallible human ways after Jesus’s life.”

“Faith in something,” he has written in several books, “is an inducement not to dormancy but to action.”

In 2015, Mr. Carter said he was feeling unwell while monitoring elections in Guyana. When he returned to Georgia, doctors found a small mass on his liver, which turned out to be malignant.

After the mass was removed, doctors discovered that the cancer had spread to his brain.

The prognosis was grim, particularly given his age at the time, 90. But he began an aggressive treatment regimen for metastatic melanoma that included a drug that had been approved only months before he started on it.

Four months later, he announced at Sunday school that scans showed he was free of the disease.

Mr. Carter’s understanding of mortality was anything but abstract.

His father, brother and two sisters died of pancreatic cancer. His mother, Lillian Carter, died of breast cancer. She was 85 when she died, but Mr. Carter noted that the others had died at relatively young ages — his father, James Carter Sr., was 59; his sister Gloria was 64; his sister Ruth was 54; and his brother, Billy, was 51.

His grandson, Jeremy, died in 2015 of a heart attack at the age of 28.

Mr. Carter recounted how his brother and mother kept their sense of humor, even as they suffered. He also admired the unflagging faith of his sister Ruth, an evangelist and spiritual healer.

In his final years, Mr. Carter had become a source of inspiration to many — and of frustration and worry for those closest to him — for the stubbornness in how he pressed ahead with his work, despite his illness and age.

In 2019, he was bruised and bandaged with a black eye after a fall at home, yet hours after the fall, he was in Nashville, helping to assemble porches on homes being built by Habitat for Humanity. A few weeks later, after fracturing his pelvis in another fall, family members and aides were adamant that he should cancel his Sunday school lesson. He perched himself before the congregation and did it anyway.

That resilience was apparent again after the Carter Center announced in February 2023 that he had entered hospice care. Many believed the end was rapidly approaching. Yet, once again, Mr. Carter defied others’ expectations. He celebrated another anniversary with his wife, Rosalynn, in July of that year, and his 99th birthday in October.

When Mrs. Carter died in November 2023 at the age of 96, Mr. Carter attended her funeral services, which was a display of his frailty as well as the strength of his devotion to his wife and his resolve to be there for her.

Aging is difficult. That’s true even for a former president with access to the best medical care and the constant support of staff.

Well into his 90s, Mr. Carter continued trotting around the world, teaching, writing and keeping up with his hobbies, including bird watching. But eventually, time caught up with him. The coronavirus pandemic pinned him down even more. He spent his final years with Mrs. Carter in the same modest home where he’d lived for decades.

In Plains, the tiny Georgia town where Mr. Carter’s house was just off the main road, his death was the cause of deep sadness. But there was a twinge of another sentiment, not quite relief but something close to it — a feeling that after such a long, productive and varied life, he had earned his rest.

His death created a void in the world, in his community, in his family, according to many who knew him and many others connected to him only through his legacy. Despite that, many in Plains also believed that his death was not an end but a transition to the eternal life that he remembered the pastor preaching about.

That’s what he believed, too.