Sergent suggested that the Israelites were poisoned by hemlock seeds that the quails had ingested. He was able to reproduce an experimental poisoning in dogs that were fed Algerian quail that had eaten hemlock seeds. However, in no case was the illness fatal.
Do not waste good things on people who will not appreciate them. This proverb is adapted from a saying of Jesus from the Gospels, “Cast not pearls before swine.” Jesus appears to be warning his disciples to preach only before receptive audiences.