Curses, like chickens, come home to roost

Here ‘come home to roost’ means ‘recoil upon the originator’, just as when a stone thrown up into the air comes down on the head of the thrower. A curse is the utterance of an evil wish. ‘May you be run over by a bus!’ The proverb means that curses are less likely to injure the person cursed than the curser himself – it is who is run over by a bus.