“This is a question that continues to bother me,” Mr. Fritz said. “Even when the police launched their assault, they didn’t try to kill us. There had been exchanges, something that reminded them of humanity — so they didn’t kill us. As my brother said, they were replete with death.”

Mr. Fritz had been on the Bataclan’s second floor balcony when the killing started. Very quickly he realized what was going on. The bodies had begun to pile up in the pit. “The odor of blood and gunpowder, very strange,” he recalled.

He attempted to call the police emergency number on his cellphone, but there was no answer. Still, he has nothing but praise for the police that night. “Superhumans,” Mr. Fritz called them.

As people fled the second floor, one of the terrorists shot at them while they descended the stairs.

When the killing moved upstairs, Mr. Fritz made a run for an open window and tried to get to the roof of the Bataclan. In vain. Hanging from the window, high above the street, he was sure that night was his last. “How am I going to die?” Mr. Fritz recalled asking himself. “Will I fall?”

One of the terrorists saw him and ordered him to climb back in, saying that “he had just killed 100 people and one more would not make any difference.” Mr. Fritz complied.

“I came down from the window and I remember looking into his eyes, and he had beautiful blue eyes, blue like the sky, there was something magnificent about his eyes. The Kalashnikov was big. He said, ‘Do you believe in God? Where is your God now?’ ”