Absolutely nothing, which is the point. While some ideas regarding ethics may be timeless, knowledge about the universe and its workings is cumulative. As a result, any attempt to use the literal language in religious texts that are over a thousand years old as the source of all wisdom is doomed to fail.
In case you are wondering, this was prompted by an article in the New York Times which explained how IS justifies raping and enslaving women and even underage girls on the basis of passages from the Koran.