Ranieri ST., an Italian ascetic of mediaeval times, was born, in or about the year 1100, of a noble family of Pisa. In his youth, the Romish legends say, he hadl a vision: an eagle appeared to him, bearing in his beak a blazing light, and said, "I come from Jerusalem to enlighten the nations." But Ranieri refused to heed this call to a religious life, and gave himself up to pleasure. But, in the midst of his debaucheries, he was one day surprised by the visit of a holy man, who persuaded him to desert his sinful life. Soon he embarked for Jerusalem, where he took off his own garments, and wore the schiavina, or slave-shirt, ever after in token of humility. For twenty years he was a hermit in the deserts of Palestine, and during this time is reiputed to have had numberless visions. On one occasion, he felt his vows of abstinence to be almost more than he could keep. He then had a vision of a golden vase, set with precious stones, and full of oil, pitch, and sulphur. These were set on fire, and none could quench the flames. Then there was put into his hands a small ewer of water; and when he turned on but a few drops, the fire was extinguished. This vision he believed to signify human passions by the pitch and sulphur, but the water was the emblem of temperance. IHe then determined to live on bread and water alone. His reverence for water was very great, and most of his miracles were performed through the use of it; so that he was called San Ranieri dell' Acqua. But when he tarried with a host who cheated his guests by putting water in his wine, the saint did not hesitate to expose the fraud; for he revealed to all present the figure of Satan, sitting on one of the wine- casks, in the form of a huge cat with the wings of a bat. He did many miracles after his return to Pisa, and made converts by the sanctity of his life and example. When he died (July 17, 1161), many miraculous manifestations bore witness to his eminent holiness. All the bells in Pisa were spontaneously tolled; and the archbishop Villani, who had been sick in bed for two years, was cured to attend his funeral. At the moment in the funeral service when it was the custom to omit the Gloria in Excelsis, it was sung by a choir of angels above the altar; while the organ accompanied them without being played by any perceptible hands. The harmony of this chant was so exquisite that those who heard it thought the very heavens were opened. He was buried in a tomb in the Duomo. After the plague in Pisa in 1356, the life of this saint was painted in the Campo Santo by Simone Memmi and Antonio Veneziano. These frescos are most important in the history of art, and consist of eight scenes from the life of St. Ranieri:
1. His conversion; 2. He embarks for Palestine; 3. He assumes the hermit's dress; 4. He has many temptations and visions in the desert; 5. He returns to Pisa; 6. He exposes the fraud of the innkeeper; 7. His death and funeral obsequies; 8. His miracles after death.
— Mrs. Clement, Hand-book of Legendary and Mythological Art, s.v.