The number 3: Collective triaphilia or divine punishment from God
People often say bad luck, or death, comes in threes. While some medical professionals attribute this to a collective triaphilia (the belief that certain events occur in three’s), others suspect a more mystical history, specifically, one based in religion. The number three represents the Holy Trinity in the Catholic church (along with the triangle), and so to take it for granted was deemed an insult to God worthy of divine punishment, as well as making a person liable to fall into the clutches of the devil. With this fear in mind, the superstition is thought to have arisen during the time of war, when soldiers believed lighting three cigarettes with one match would bring disaster. The match, as well, was thought to represent the fires of Hell awaiting the transgressor’s now damned soul. There are a few instances of the phrase being used in the 1930s, but it’s possible the superstition is even older.