Agios Dimitrios: Why occurs the horseman on a red horse?

Agios Dimitrios, inspires with his life, martyrdom, and miracles of the orthodox icon painter, who composes the relevant images…
Agios Dimitrios is often depicted in front of the Μαξιμιανό, in prison, blessing st. Nestor, but in addition because of Agios Dimitrios is one of the military and at the same time protector of Thessaloniki, which many times saved from various dangers, the performances, in which the saint is represented in the military, either on foot or rider, is common in orthodox iconography.
Between these hagiographies of the Saint Demetrios is depicted on horseback on a red horse, in contrast with the white horse of Saint George.
In this picture agios Dimitrios is presented to a rider in military uniform on red horse murder with the spear of the tsar of the Bulgarians Σκυλογιάννη. This is the miracle that happened in October of 1207 outside the walls of Thessaloniki.
The tsar of the Bulgarians Ιωαννίτζης that the Byzantines called Σκυλογιάννη, was assassinated during the delivery of agios Dimitrios, when he was besieging the city of Thessaloniki. In the face of agios Dimitrios Thessaloniki sees always the protector, the rock. (Ηαπελευθέρωση of the city from the Turks in 1912 coincided with the feast day of saint).
Fairly agios Dimitrios is called the exceptional of the Church “the great guard of Thessaloniki, the ρύστης in the κινδύνοις the excellent, champion the κράτιστος” (Κανώνδεύτερος). Another Rule, composed by Symeon of Thessaloniki, agios Dimitrios reportedly says in charge of the country, Thessaloniki’ “…fear not, they, patrice, me, me occupying your enemies for all smite in Christ and stand guard in the τιμωσανμε”.
Justly observed, that of all the images of St. Demetrius, the image of the equestrian saint is loved more, because it embodies the Greek ideals of παλληκαριάς and gallantry. In the consciousness of the faithful of saint Demetrios is not only, in the exceptional, “kripis unconquered and foundation unbreakable and protector, settler and a proponent” of the city of Thessaloniki, and “largely and oftentimes κινδύνοις χαλεποίς Locals head”, but ομέγας champion of the world.

For this sing of our Church, “Great εύρατο in the κινδύνοις, υπέμαχον the world, αθλοφόρετα nations τροπούμενον. As they Λυαίου καθείλες the power, in the model θαρρύνας Nestor, so Holy, great martyr Demetrius, Christ our God, begging, δωρήσασθαι us his great mercy” (introit of the holy)
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