In general, Tuesday is considered an occult day, that is, rough and dangerous for these peoples. When Tuesday and the 13th coincide it is considered very unlucky and dangerous day.
The Spanish express the day with the proverb “En martes, ni te cases ni te embarques” (“On Tuesday, do not get married and do not start a journey”). Something similar applies to us, when the conservatives on Tuesday avoid starting any work, traveling or engaging. Instead, Tuesday is the perfect time for magic.
According to Greek tradition, Tuesday is considered rude, as on this day Constantinople fell to the Ottoman Turks (Tuesday, May 29, 1453). As the “father” of Greek folklore Nikolaos Politis (1852-1921) observes, this interpretation is retrograde, since the contemporaries in the Fall also attributed that national disaster to the disastrous effect of the day. Evidence for this prevention has existed since 1164.
According to Nikolaos Politis, the explanation of superstition must be sought in astrological predictions. According to them, the planet Mars is dominant on Tuesday, while at some time of the day (the “bad time”) it prevails together with the planet Saturn. That is why this time is becoming especially dangerous. But because no one can identify it, the whole of Tuesday is treated as an occult day.
13 is the most unfortunate number, which breaks the harmony of 12 (12 Gods of Olympus, 12 feats of Hercules, 12 tribes of Israel, 12 disciples of Christ, 12 Imams, etc.). The addition of the number 1 forms the beginning of a new cycle. The unknown, represented by the number 13, causes people anxiety and so they began to associate it with unfortunate events.