A very perplexing word today

I get the Word A Day mailing. Here's the word for today:

asperse
PRONUNCIATION: (a-SPURS)

MEANING:
verb tr.:
1. To spread false and malicious charges against someone.
2. To sprinkle with holy water.

ETYMOLOGY:
From Latin aspergere (to sprinkle), from ad- (toward) + spargere (to strew).


Now, what I want to know is how a word got such two radically different meanings?
Any ideas?