In this parsha, Shelach Lecha, Hashem tells Moshe to send meraglim, or spies, out to Eretz Yisrael. Rashi tells a parable: A person is looking to buy a donkey and asks to try it out to see if it won’t die while it is being ridden. When the seller says yes, the buyer decides to buy it anyway, because if the seller was trying to cheat the buyer, he wouldn’t let him try out the donkey and just would want the money.
When the spies came back, they say loshon hara, or gossip, about Eretz Yisrael. What they said was the truth; it’s just that they cast it in a negative light. What they did, however, was say it publicly, instead of privately telling Moshe. Because all of Bnei Yisrael heard, they got scared.
The meraglim did the wrong thing – they should have been discreet. From this we learn the value of modesty – not just how we dress, but how we act, too.
[Sources: Mrs. Natalie Williams, parable heard from Ariel Weinreich]