People use the phrase "gospel" colloquially to mean "the bible," which is what I said. You're really splitting hairs here.
No, I've got to agree with Faith and ICANT here. The gospel is the good news about Jesus Christ. And this is not merely technically accurate, but in all my experience it is the colloquial usage too. The book of Jeremiah, for example, is not "the gospel", and an Orthodox Jew expounding on that book would not be preaching the gospel.