Say what?

“Jesus didn’t die,” David said.
“Excuse me?”
“Jesus never died.”
This was the same child who had rattled off, as though he had memorized it, that Jesus had died for his sins. He’d said it just the week before. “Why don’t you think he died, David?”
“They just put nails through his hands. That wouldn’t kill you.”
JC explained, in gorier detail than I would have done, the way one dies when one is crucified—not from the pain and blood loss of having one’s hands nailed to a piece of wood, but slow suffocation from one’s chest not being able to expand properly. “Not to mention,” he concluded, “they beat him within an inch of his life before they put him up there.”
“Then how was he able to walk around later?” David wanted to know.
“That’s the miracle,” I said.

How could someone who had attended church weekly for ten years not know that? Surely he had seen The Passion. Surely someone had told him, at some point, about Jesus dying for his sins. How can we raise children to be believers when we don't explain to them the miraculous nature of Jesus' life?