The emperor Constantine, on his conversion to Christianity, brought the whole Roman empire with him. At the Council of Nicea the official text of the Bible was established under his jurisdiction, together with the Creed, the main lines of official theology, and a considerable body of police to enforce them.
The mother of the emperor, Saint Helen, discovered the burial site of Jesus, and on the site the entire true cross, complete with the nails still in it. She sent the nails of the cross to her son, the emperor, who had the nails melted down and from them made the bit (the metal piece that goes into the horse’s mouth, and is attached to the reins) for his war horse.
C-Span, October 25, 2009
Interpretation does not seem necessary.