The inscription reads:
The Legend of St Christopher
"Child why are you so heavy? It seems to me that I am carrying the weight of the world".
"You carry not only the world" responds the Child, " but He who created the world".
"I am Christ your God and Master".
The following is a rough translation from a out-of-publication French book on the life of St Therese in pictures.
The legend of Saint Christopher is the gradual development of the name "Christophoros" which means "Christ-bearer" in Greek. The name, in times past, called to mind the mysterious privilege of being able to carry Christ in ones heart. In the 11th century a story circulated of a malfaiteur (criminal or wrong-doer) sometimes called Auferus (brigand), or Reprobus (the cursed or condemned) and was baptized Christophorus (Christopher) after converting.
According to The Golden Legend, a work popularized during the 13th century, the man who carried the Saviour on his shoulders was thought to be a giant.
One night, according to the legend, he was hired to carry a child across the river pass on his shoulders.To his astonishment the child became heavier and heavier as Christopher advanced farther out into the river. He grabbed hold of a floating tree branch to help support himself and proceeded across. Eventually the child revealed his true identity, "I am Christ, King of Heaven and Earth." Then the Christ Child offered proof. He told Christopher to plant the barren tree branch in the ground. As he did this it transformed into a palm tree full of dates. The legend surrounding this herculean Christian developed rapidly after that. St Christopher was called on to protect against the misfortune most feared in the Middle Ages- that of a sudden death without a last confession. According to popular belief it was enough to have seen his image in order to be protected for the entire day so it was beneficial to carry his image all day long to avert danger. Larger than life images of St Christopher, in painting and sculpture, grew out of this tradition. They were placed inside and outside the churches in order to make Saint Christopher accessible to all.
Because St Christopher was the protector against sudden death, he was invoked during the plague. Several guilds made him their patron saint: for example, the musketeers (an early modern type of infantry soldier) and, in our day, hikers or mountain climbers, auto, air and water travelers, as well as pilgrims, gardeners and horticulturalists. Many paintings and statues of St Christopher were systematically removed from churches during the time of the Reformation and after the Council of Trent. Recently, those who invoke his protection for automobile travel has regained popularity.
If you would like to read some interesting research from another source google "Understanding the Dog- Headed Icon of St Christopher".