Though he had been grievously harmed, Mr. Jerome-Parks bore no bitterness or anger.

“You don’t really get to know somebody,” said Ms. Leonard, the friend from church, “until you see them go through something like this, and he was just a pillar of strength for all of us.”

Mr. Jerome-Parks appreciated the irony of his situation: that someone who earned a living solving computer problems would be struck down by one.

He grew closer to his oncologist, Dr. Berson, who had overseen the team that caused his injury. “He and Dr. Berson had very realistically talked about what was going to happen to him,” said his father, James Parks.

Ms. Jerome-Parks, who was providing her husband round-the-clock care, refused to surrender. “Prayer is stronger than radiation,” she wrote in the subject line of an e-mail message sent to friends. Prayer groups were formed, and Mass was celebrated in his hospital room on their wedding anniversary.

Yet there was no stopping his inevitable slide toward death.

“Gradually, you began to see things happening,” said Ms. Weir-Bryan, the friend from Toronto, who helped care for him. “His eyes started to go, his hearing went, his balance.”

Ms. Giuliano, another of the couple’s friends, believed that Mr. Jerome-Parks knew prayer would not be enough.

“At some point, he had to turn the corner, and he knew he wasn’t going to make it,” Ms. Giuliano said. “His hope was, ‘My death will not be for nothing.’ He didn’t say it that way, because that would take too much ego, and Scott didn’t have that kind of ego, but I think it would be really important to him to know that he didn’t die for nothing.”