Panagia Axion Estin
Panagia Axion Esti(Greek: Άξιον εστίν, Slavonic: Достóйно éсть, Dostóino yesť), or It is Truly Meet.
Axion Estin is also the name given to this icon of the Theotokos before which, according to tradition, the Axion Estin hymn was revealed. It stands in the high place of the altar (sanctuary) of the katholikon (main church) of Karyes on Mount Athos.
According to tradition, an Elder and his disciple lived in in a cell on Mount Athos. One Saturday night the Elder left to attend the All-Night Vigil in Karyes. He told his disciple to chant the service alone. That evening an unknown monk who called himself Gabriel, came to the cell, and they began the Vigil together. During the Ninth Ode of the Canon, when they began to sing the Magnificat, the visiting monk chanted the first part of the hymn, "It is truly meet…" as normal, but then he continued with, "More honorable than the Cherubim…". As he sang, the icon began to radiate with Uncreated Light. When the disciple asked the visiting monk to write the words of the new hymn down, he took a roof tile and wrote on it with his finger, as though the tile were made of wax. The disciple knew then that this was no ordinary monk, but the Archangel Gabriel. At that moment and the angel disappeared, but the icon of the Mother of God continued to radiate light for some time afterward.
The Eleousa ("merciful") Icon of the Mother of God, before which the hymn "It Is Truly Meet" was first chanted, was transferred to the katholikon (main church) at Karyes, known as the Protaton. The tile, with the hymn written on it, was taken to Constantinople when St. Nicholas II Chrysoberges was Patriarch (984-996).
Since that time the icon has been considered the protector of the Holy Mountain and its holiest object.