Recently, of the people I've asked, no one knew what this phrase meant. I am by no stretch of the imagination a Christian scholar, so I'd assumed that if I knew it, everyone must know about it.
Some other definitions:
I agree with the Bartleby definition the most, but I'd define it as giving something of worth to someone (or thing) who can't appreciate it.
Well, there ya go. I hope you feel enlightened. If not, well... y'know :)