"A Visual Demonstration" joke

A minister decided that a visual demonstration would add emphasis to his Sunday sermon. He put four worms into four separate jars.
The first worm was put into a jar of alcohol.
The second worm was put into a jar of cigarette smoke.
The third worm was put into a jar of semen.
The fourth worm was put into a jar of good, clean soil.

At the conclusion of the sermon, the minister reported the following results.
The first worm in alcohol - dead.
Second worm in cigarette smoke - dead.
Third worm in semen - dead.
Fourth worm in good clean soil - Alive.
The minister asked the congregation - "What can we learn from this demonstration?

A little old woman in the back quickly raised her hand and said;
As long as you drink, smoke and have sex, you wont have worms.