The content is very interesting. This is the second book I have read on Martin Luther, and this portrays him in a more "real" sense.
The content, however, is a touch dry. It's not so much that I don't understand the psychology; it's more that Erikson uses really long sentences that don't parse well. I find myself re-reading to get the gist of his meaning.
I got this book for under $4, and you can too.