can of worms

A creative Irish priest decided that a visual demonstration would add emphasis to his Sunday sermon. So at the start of his sermon, he placed four worms into four separate jars. He put the first worm into a container of alcohol. He put the second worm into a container of cigarette smoke. He put the third into a container of chocolate syrup. And the fourth worm he placed in a container of good clean soil.

At the conclusion of the sermon, the priest reported the following results:
The first worm in alcohol - Dead.
The second worm in cigarette smoke - Dead.
Third worm in chocolate syrup - Dead, too.
The Fourth worm in good clean soil - Alive.

So the gratified priest turned around and dared his congregration. "What can you all learn from this demonstration?" he thundered.

A timid voice up the back shouts: "As long as you drink, smoke and eat chocolate, you won't have worms!"