Cappadocia (in eastern Turkey) is virtually devoid of Christians now, but in 1840, when St Arsenios was born there, there were still vital Orthodox communities. He became a monk and was sent to his native town, Farasa, to serve the people. He became known as a mighty intercessor before God, praying for all who came to him, Muslims as well as Christians. His countless miracles of healing became known throughout Cappadocia; those who could not come to see him would sometimes send articles of clothing for him to pray over. He became known as Hadjiefendis, a Muslim term of honour for pilgrims, because he made pilgrimage to the Holy Land every ten years on foot. He never accepted any gifts in return for his prayers and healings, saying ‘Our faith is not for sale!’

“He concealed his holiness as much as he could beneath a rough and sharp-tempered exterior. If anyone expressed admiration for him, he would reply "So you think I'm a saint? I'm only a sinner worse than you. Don't you see that I even lose my temper? The miracles you see are done by Christ. I do no more than lift up my hands and pray to him." But as the Scriptures say, the prayers of a righteous man avail much, and when St Arsenios lifted up his hands, wonders often followed.

“He lived in a small cell with an earthen floor, fasted often and was in the habit of shutting himself in his cell for at least two whole days every week to devote himself entirely to prayer.

“Father Arsenios predicted the expulsion of the Greeks from Asia Minor before it happened, and organized his flock for departure. When the expulsion order came in 1924, the aged Saint led his faithful on a 400-mile journey across Turkey on foot. He had foretold that he would only live forty days after reaching Greece, and this came to pass. His last words were "The soul, the soul, take care of it more than the flesh, which will return to earth and be eaten by worms!" Two days later, on November 10, 1924, he died in peace at the age of eighty-three. Since 1970, many apparitions and miracles have occurred near his holy relics, which reside in the Monastery of Souroti near Thessalonica. He was officially glorified by the Patriarchate of Constantinople in 1986.”

— Source: Orthodox Parish of St John of Kronstadt (UK)

The primary source for the life of St Arsenios is Saint Arsenios the Cappadocian, compiled by Elder Païsios of the Holy Mountain, who was baptized as an infant by the Saint.