Definition
To offer something valuable or of high quality to someone who does not appreciate or understand its worth.
Trying to explain the severity of climate change to those who don't care about the environment is like casting pearls before swine.
I spent a lot of time preparing this report, but my boss didn't even look at it; I felt like I was casting pearls before swine.
Explaining the nuances of the painting to someone who knows nothing about art is really like casting pearls before swine.