Jesus told parables. When he wanted to say something really profound about God, he went into parable. I don't find it surprising then that when earliest Christianity wanted to say something profound about Jesus, they went into parable too. That doesn't mean everything is a parable. When it says Jesus was in Nazareth I don't think that's a parable, I think Jesus was in Nazareth. When it talks about Jesus walking on the water, I don't think that's the point at all, I think the point is that the church without Jesus sinks.