(Thanks for the suggestions in the comments on the plots.)
First I'll plot the number of contradictions in each book by testament.
Notice that the gospels have the most contradictions in the New Testament, as does Genesis in the Old. No big surprise there. But they are also rather big books. What happens if we take size into account?
We can do that with the Contradiction Index, which is just the number of contradictions per 100 verses. Here's what that looks like.
And here's a log-log plot of the number of contradictions versus the number of verses.
And now on to cruelty!