For Victor Kaudo, a rights activist in Malindi who visited Shakahola in March, the freedom granted preachers like Mr. Mackenzie has gone too far. Tipped off by defectors from the cult, Mr. Kaudo found emaciated believers who, though in the throes of death, cursed him as “an enemy of Jesus” when he tried to help.

A starving woman, her head shaved on orders from the cult leadership, flailed angrily on the ground as Mr. Kaudo approached offering sustenance, a video he recorded showed.

“I wanted these starving people to survive, but they wanted to die and meet Jesus,” Mr. Kaudo recalled. “What do we do? Does freedom of worship supersede the right to life?”

Mr. Mackenzie has told investigators that he never ordered his followers not to eat and merely preached about the End Times agonies prophesied in the Book of Revelation, the final chapter of the New Testament. He was arrested in April, set free and then quickly rearrested. He is under investigation over accusations of murder, terrorism and other crimes. His lawyer declined to comment.

Appearing briefly before a court in Mombasa this month, Mr. Mackenzie, 50, wearing a pink jacket, cut a jaunty figure as he waved imperiously from inside a metal cage to get the magistrate’s attention. The magistrate ignored him and extended his detention.