Is Aslan Safe?

I'm reading CS Lewis' The Lion, the Witch, and the Wardrobe before I watch the movie adaptation. Upon first hearing about Aslan (the original Lion King), one of the children asks if Aslan is safe. The reply (p75-76) is well worth considering:

'If there's anyone who can appear before Aslan without their knees knocking, they're either braver than me or else just silly.'

'Then he isn't safe?' asked Lucy.

'Safe?' said Mr. Beaver. 'Don't you hear what Mrs. Beaver tells you? Who said anything about safe? 'Course he isn't safe. But he's good. He's the King, I tell you.'