Today 30 January 2019 we celebrate and honor in the Greek Orthodox Church the Three Hierarchs.
The celebration of the Three Hierarchs started in the 11th century when Constantine III Monomachus reorganized the Law School of Constantinople. At that time there were three Saints who were seen as the Saints of education namely Gregoreios the Theologian, Ioanis Chrysostom and Vasileios the Great. During the reorganization the reorganizers could not decide which one of the Saints to place on top and this resulted in a division of the Christians so the ones were called the Gregorites, the others the Ionanites and others the Vasilites.
Until John Mavropos, who was then the Metropolitan of Euchaite, had a vision in which he saw the three Saints. They told him that they are equal to eachother and that they can’t be seperated, that between them there is neither the first nor the second, but if you see one, the two others are next to him. So John Mavropos gave orders to stop the quarrels and stop dividing them for they cannot be seperated and so these three Saints became the Three Hierarchs, the three Saints of education and on the day of their celebration all schools are closed.
From the 11th century on you can also see them together on icons and they are honored every year on the 30th of January.