Robert Jenson and others on the devil

Still thinking about the existence of the devil. Saw this stuff ...

Did Rudolf Bultmann say something interesting about the devil not existing? Did Karl Barth agree with him? ... Angels and demons, Barth and Bultmann

You can read the first chapter of The Devil: A Very Short Introduction by Darren Oldridge online here.

And Robert Jenson writes this about the devil in an introduction to Sin, Death, and the Devil by Carl E. Braaten ...

[...] And finally there is that incarnation of vacuity, the devil. Karl Barth puzzled normal minds by saying that the devil was a myth. Folk were alarmed: Barth, they said, doesn't believe in the devil. But of course that was just the point: one believes in God, and in another sense in such things as salvation, and just possibly sometimes in other persons or even in certain facts about the world, but assuredly not in the devil. Barth's point was that not believing in the devil is the appropriate relation to the devil's mode of existence. That the devil is a myth doesn't mean, in Barth's thinking, that he doesn't exist; it means that he exists in a particular way, as the ordained object of denial.

Putting it my way, the only description possible of the devil is a description of what is the matter with him. The only predicates of the devil are his deficiencies, for the devil is the angel who refuses to be one ....

All I've read or seen on the devil, from the satirical CS Lewis version to the really scary Viggo portrayal, has just disturbed me. I can't imagine a good God who would allow a being like the devil to exist.