[quote=adnauseum]I suggest it means don’t denigrate the good news by offering it to someone who isn’t disposed to listen to it.
If you find someone who is openly hostile to the gospel, being sarcastic, disrespectful, then walk away. But if they seem to have a genuine interest, then present the treasure to them.
Jesus sent the disciples out to spread the good news, but he told them if they were not welcomed in any town, to kick the dust from that town off their shoes and move on.
This is my take on it as well. It goes hand in hand however with something else that St. Peter wrote:
But even if you do suffer for righteousness’ sake, you will be blessed. Have no fear of them, nor be troubled, but in your hearts reverence Christ as Lord. Always be prepared to make a defense to any one who calls you to account for the hope that is in you, yet do it with gentleness and reverence; and keep your conscience clear, so that, when you are abused, those who revile your good behavior in Christ may be put to shame. For it is better to suffer for doing right, if that should be God’s will, than for doing wrong. 1 Peter 3:14-17