There's plenty of Christianity-as-a-source-material media out there. The obvious example is the Narnia series, but LotR was also highly inspired by Tolkien's faith. Many pre-20th century Western works are based in Christianity (when the world was less secular). It's fallen out of favor recently so most Christian works that make it big are Evangelical, like the Left Behind series.

As another comment mentioned, there actually is a Bible stories manga/anime, but it's pretty old.