Today we are going to the Bible for our expression, Pearls before swine.
This expression is usually expressed in the negative proverbial form — 'Don't cast your pearls before swine' — and is found in the Bible: Matthew 7:6, in what is known as the Sermon on the Mount.
It first appeared in English bibles in Tyndale's Bible, 1526:
Nether caste ye youre pearles before swyne.
By the way, the swine in the expression refers to pigs, and the implication is that valuable items such as pearls or precious stones should not be thrown to pigs, since they won’t have any use of them.
It had existed in the language for some time before that, in various forms. It may have migrated from France, as it is found in a Middle French text from 1402 as 'jeter des perles aux pourceaux'. It is also found in Middle English, in Langland's Piers Plowman, which is of uncertain date, but appeared around the same time:
Nolite mittere, Man, margerie perlis Among hogges...
The biblical text is generally interpreted to be a warning by Jesus to his followers that they should not offer biblical doctrine to those who were unable to value and appreciate it.
In modern English, the expression has come to mean items of quality offered to those who aren't cultured enough to appreciate them.
Examples:
Giving him advice is just casting pearls before swine. He doesn't listen.
To sing for them is to cast pearls before swine.
