Hmm, I've just seen Trisia's response from earlier. I guess you could use "beyond the grave" in that sense, but it is much more common to hear it in the context of ghosts.
If you were trying to say that an author's words were still being heard after her death, then you would more likely say something like "Her words are still as relevant today as they were in the author's time" not "Her words are heard from beyond the grave."
Trisia and Tegs, thanks for your quick answear.
I haven't a complete sentece. I just listened somebody speaking. I thought it was an expression and I understood that means "gossip" or "talk from behind the people". Does it make sense to you?
Perhaps the phrase could be considered to mean that a suggestion, proposal, or opinion written or spoken in the past, by someone now dead, could be applicable to a discussion or problem of the present time.