David, suffering from non-Hodgkin's lymphoma, is scheduled to begin an experimental course of treatment next week that involves the transplant of stem cells in his bone marrow.
In an e-mail note sent the week after the concert, David offered thanks - and words of hope - to a wide circle of friends who have supported him and his wife, Anne Marie.
"Anne Marie and I benefited [from the concert], indeed, but it seems as though everyone present received, as well," he said. "It was a time of collective exhalation. Mom always says, 'Offer it up,' and on this day of giving, I think those present were also allowed to let some things go.
"With each breath I take, I choose to believe," he said. "Expect miracles, folks. And remember, we each are living one."
-Mark Sullivan