I recently read, The Swerve about On the Nature of Things by Lucretius. It was very well written has made reading On the Nature of things that much more enjoyable. Getting that context and backstory was -ironically- a godsend. While I agree with his point about coming into conversation late and missing some of the meaning, with some books you just have to accept that that ship has sailed and look for the help of somebody who studied the work. To me this is why historical writers are so important, we put a lot of trust in them.
