The answer to this riddle is Nothing. When you break down every section of the riddle, the word that best fits in is “nothing.” For instance, let’s start with “what is greater than God.” Everybody knows God is a supernatural being with superior powers, and he is the supreme being. So, it would be right to say nothing is greater than God.
To the second section of the riddle, we all know the devil is the evilest being that was created by God, so it would be right to say nothing is eviler than the devil. To the third section of the riddle, we all know poor people are those with no money or possession, so it would be right to say the poor have nothing.
In the fourth section:” the rich need it,” we all know the rich are wealthy people, so it would be right to say the rich need nothing. And to the last section of the riddle, it would be right to say “if you eat nothing, you will die.”