On this day in history in 533 a man named for a pagan god became the pope.
Until that time, all pontiffs had attached their own name to the job instead of the other way around. The only reason numbers had been added was if the name of the current pope happened to be the same as a previous one (sort of like when you’re in first grade and there are three different girls named Jennifer). Nobody had thought of changing their name, even if it was silly (like Hilarius).
|Pope John II,|
pointing to God instead of Mercury
But when Mercurius was elevated to the position, he recognized the impropriety of the name he had been given at birth. How could he could be revered as closest person to God by all of Christendom if the very mention of him brought another god to the minds of worshipers? It would be like a pope today taking the name “Satan I” when he became pope. There was nothing else he could do; he had to ditch his name.
Being named after a god meant that you were protected and blessed by that god. “John” is a theophoric name meaning “Yahweh is gracious.” So Mercurius became Pope John II.
Today, everyone changes their name when they take the job, but John II had a very good reason to start the trend. Although I think these days it’s more “leaving the man you were behind and becoming the man worthy to lead the church” than “my name is too mercurial to be appropriately papal.”