spoken words can't be retrieved

A farmer insulted his neighbor. Realizing his mistake, he went to the preacher to ask for forgiveness. The preacher told him to take a bag of feathers and drop them in the center of town. The farmer did as he was told. Then the preacher asked him to go and collect the feathers and put them back in the bag. The farmer tried but couldn't as the feathers had all blown away. When he returned with the empty bag, the preacher said, "The same thing is true about your words. You dropped them rather easily but you cannot retrieve them, so be very careful in choosing your words."