David seemed to always put himself in a position to help strangers and the Hulk was the muscle when words couldn't convince. Big part of show was how compassionate David was even sometimes risking being found out to right a situation.
shareYes, David was a true sad angel in human form, helping the good people in need, while the Hulk was an angry avenging angel punishing the crooks or evildoers to get them off the streets, and into jail!
Like Johnny Appleseed, he planted seeds of goodness where he could, then moved on...
The concept is very old, but the phrase may have been coined by Lily Hardy Hammond in her 1916 book In the Garden of Delight.
Pay it forward is such a beautiful idea. It would be an interesting premise for an anthology TV series. Has it been done? It sounds a little like the 1995 UPN TV show "Marker" starring Richard Grieco.