That's an easy question for most of us to answer. It's one of the few things that we can all agree on: it is wrong always and everywhere to burn to death anyone for any reason whatsoever.
And if a man take a wife and her mother, it is wickedness: they shall be burnt with fire, both he and they; that there be no wickedness among you.Notice that God tells us to burn to death all three: man, wife, and mother-in-law. It may have been the man's idea, but we must burn all three anyway. (Couldn't we try counseling first?)
Is there anyone that really believes this is a good idea? Is there anyone who thinks it was a good idea a few thousand years ago? Will it be a good idea a few thousand years from now?
A god who commands people to burn other people to death is not a good god. This verse alone should be enough show that the Bible was not inspired by a kind and loving god.