Specifically, Lazarus was unable to take a drop of water to the rich man.
BUT, when the rich man asks that Lazarus be sent to His brothers, the argument is NOT, "That's impossible - there's a great gulf fixed," but rather, "They won't listen."
As I tried to indicate, I did read it. I still don't see a text showing its relevance to communication between us on earth and the saints in heaven. It would be hard even to make the "They won't listen," argument apply.
I see no relevance. What specifically am I missing?
1st Samuel 28 gives a pretty good summation of what happens when one appeals to the dead saints for assistance.