Honey is almost pure sugar (mainly glucose). Sugar, like anything that dissolves in water, will draw water from anything else into it in order to partially dissolve itself. This includes the cytoplasm of bacteria, or the blood of animals. Obviously, having the water sucked out of you is deadly, so honey never spoils, because it is a natural preservative. In other words, it's a demonstration of the fact that anything in high enough concentration is poisonous. Of course, diluting honey removes its toxicity, and humans are big enough that the amount of honey we can eat gets diluted in our stomach and bloodstream that it's no longer toxic - in fact, it's healthy. But if you've ever eaten a lot of honey, you will notice yourself getting thirsty, and this is why: it's using up all of the available water we use in our own bodies as a solvent, so you need more water.

Salt has been used as a preservative and works by exactly the same process - brine-soaked meat won't spoil either.

Honey doesn't usually spoil because it has an extremely high sugar concentration.While most microorganisms that cause spoilage eat sugars, if there is too much sugar present, it can be lethal for them, via osmotic lysis.

If you let honey sit out, uncovered, it will spoil eventually. It is very hygoscopic (absorbs water readily). Once it absorbs enough water, the sugar concentration will be low enough that it would be very delicious food for microorganisms.