I heard this riddle several years ago. I believe it is attributed to Art Linkletter. I cannot confirm it.
The kicker is that something like 80 to 90% of kids under 10 years old will correctly answer it. However, only about 15% of adults get it correct. Are you ready?
What is greater than God, more evil than the Devil, the poor have it, the rich need it, and if you eat it you will surely die.
I turned off comments to this. I will post the answer next week. If you cannot wait that long, you will just have to ask a first grader!