Why does breaking a mirror cause 7 years of bad luck?

It is believed that breaking a mirror would cause seven years of bad luck because the soul of the person who broke the mirror would be trapped inside. The superstition was said to have come from the Romans, who were the first group of people to create glass mirrors.

Many cultures, including the Greek, Chinese, African and Indian believed that a mirror had the ability to confiscate part of the user’s soul. A broken mirror would indicate a broken soul. If someone does break a mirror, it’s best to take care that no one gets cut by the shards of broken glass.