Legend and anthropology hold that some American Indian cultures believed that, if you rescued somebody, saved somebody's life, or prevented them from disaster, you were indebted to them forever. That is, the saver was beholden to the saved.
My fantasy is that the issue is that you postponed their arrival to the Happy Hunting Grounds.
In Western culture we tend to see it the other way around because of a Christian foundation, or because we want to see this life as heaven (?), but as an American physician who works for nobody - not government, not insurance, not a hospital - except my patients, I see it both ways. If I get you out of big trouble, you sort of own me as long as you want to.
A little gratitude is always welcome, of course.