Throwing salt over your shoulder is practiced in several cultures and civilizations, and the meaning differs.

In Mahayana Buddhist tradition, they throw salt over the left shoulder to prevent evil spirits from following and entering the house after a funeral.

Many cultures valued and still value salt a lot, and spilling salt has been considered to be unlucky for millennia. The ancient Sumerians did the ritual of throwing a pinch of salt over their left shoulders to nullify the bad luck of spilling salt, and soon, the Egyptians, the Assyrians, and later, the Greeks practiced that as well.

Christians also associate spiled salt with bad luck, except for them, it also means lies and disloyalty – as seen on Leonardo da Vinci’s painting The Last Supper where Judas knocked over salt with his elbow. They also believe that the devil hangs around the left shoulder, and throwing salt over your shoulder blinds him. Spilling salt, on the other hand, is seen by the devil as an invitation to take advantage of you.

People also theorize that since salt was so valuable and expensive back in the day (so much so that some civilizations even used it as currency), no one in their right mind would spill it, and if someone does, it’s the work of the devil. Throwing a small amount over your shoulder would blind the devil and teach him a lesson.