Icelandic Superstitions: “Sjö Níu Þrettán”

You are likely very familiar with the old superstition about “knocking on wood” or “touching wood”—rapping your knuckles lightly on a table or any piece of wood in order to avoid a bad outcome for a specific hope (e.g. “We should get our summer bonuses today, knock on wood”).

Icelanders take that to a new level, though. It’s not enough to simply knock on wood; you’re also supposed to say “sjö níu þrettán” (literally “seven nine thirteen”) as you knock.

This particular superstition is so common that many Icelanders do it without realising its origins.

There are numerous explanations for where “knocking on wood” came from: everything from it being a reference to touching the cross of Christ, to waking up good spirits in the wood to fight evil spirits that might undo your hopes, and even to knocking on a table being a common way for abbots to scold boastful monks at the dinner table.

The use of the numbers seven, nine and thirteen are similarly a blend of Christian and pagan origins. Seven has long been considered a magic number, stemming from adding three (a triangle) to four (a square), with their respective shapes representing the spirit world and the material world, or possibly stemming from the number of days in a quarter lunar cycle. Nine is of course the sum of three times three, the number of the Holy Trinity. Thirteen having some (usually evil) supernatural connotations does not, as popularly believed, come from Jesus and his 12 disciples; it’s even older than that, going back to the old Roman calendar which used 12 months of equal length and then one extra month added every six years. Just as Leap Day is a mild annoyance for some, the Leap Month was an even greater inconvenience, and led to 13 being associated with ill fortune.

This being the case, sjö níu þrettán is really just a Superstition Value Pack; mashing together several different superstitions at once in an effort to defend one’s best laid plans from being destroyed by the forces of chaos. It’s popularity is pretty interesting, given that Iceland is the home of the “þetta reddast” (“it’ll all work out in the end”) guiding philosophy.