The origin of this Feast is explained in the Greek Horologion of 1897: “Because of the illnesses which occur during the month of August, it was customary at Constantinople to carry the Precious Wood of the Cross in procession throughout the city for its sanctification, and to deliver it from sickness.”
On the eve (July 31), the Cross was removed from the imperial treasury and placed it upon the Holy Table of the Great Church of Hagia Sophia (which is dedicated to Christ, the Wisdom of God). From August 1 until the Dormition of the Most Holy Theotokos, there was a procession throughout the entire the city, and then the Cross was placed where all the people could venerate it.
This feast was instituted by a mutual agreement between the Greeks and Russians, at the time of the Greek Emperor Manuel and the Russian Prince Andrew, in commemoration of the simultaneous victories of the Russians over the Bulgars, and the Greeks over the Saracens. In both of these battles, crosses–from which heavenly rays blazed forth–were carried by the armies. Therefore, it was ordained that, on August 1, the Cross be carried first to the middle of the Church of the Divine Wisdom [Hagia Sophia] and afterward through the streets for the veneration of the people, as a commemoration of the miraculous help of the Cross in battle. This was not an ordinary cross, but the true Honorable Cross itself, which was kept in the church of the imperial court. On July 31, the Honorable Cross was carried from the imperial court to the Church of the Holy Wisdom, and from there it was carried along the streets, for the consecration of the earth and the air. Finally, on August 14, it was returned to the church of the imperial palace.
Because of the many diseases that occur in the month of August, the custom prevailed of old in Constantinople to carry the precious Wood of the Cross in procession throughout the city for its sanctification and its deliverance from illnesses. It was brought forth from the imperial treasury on the last day of July and placed upon the Holy Table of the Great Church of the Holy Wisdom; and beginning today, until the Dormition of the Theotokos, it was carried in procession throughout the city and was set forth for veneration before the people.
