Why is it that St. Peter's cross came to be associated with Satanism?
According to the most widely-spread belief, the Cross of St. Peter is upside down because St. Peter requested to be crucified upside down, as he didn’t deem himself worthy enough to be crucified in the same manner as Jesus. By doing so, he wanted to claim his death as his own, and not that it was for martyrdom. Thus, perhaps the symbol was attributed a negative status, and embodied a rejection of Christianity.
However, this is not necessarily the case. In no accounts of the crucifixion of St. Peter is it ever mentioned that he requested to be crucified upside down, and in only one of the mere nine accounts telling the story does it ever include feelings of being unworthy of Christ. This story is not found in any incarnation of the Bible.
Others believe that it is simply the act of “inversion”: Taking the known symbol, and reversing it to symbolize opposition. The most likely truth lies somewhere between the two.
During the time when St. Peter was crucified, Rome was under the rule of Nero–one of the most notoriously brutal of all of Rome’s emperors. During his reign, Nero prioritized the persecution and torture of Christians, believing the removal of all traces of Christianity would bring peace and prosperity to the Roman empire. In his efforts to suppress Christianity, Nero adopted the symbol of an inverted cross with broken arms, which was meant to symbolize a believed failure and degradation in choosing a Christian path.
It is no wonder that a few spin doctors may have begun to associate an upside down cross with the crucifixion of St. Peter. In reality, it’s highly illogical to believe that the Roman army would have honored a single man’s request, especially if said request was supposed to be out of respect for Christ. The Roman army was also known for wildly varying methods of torture, as well as unusual methods of crucifixion, further killing the idea that St. Peter had anything to do with it.
On a side note, you might notice that the Neronic Cross bears a striking resemblance to the symbol we know today as the “peace sign”. Gerald Holtom, the original designer of the peace sign, expressed in interviews that he wanted to avoid equating the movement against nuclear disarmament with religion due to the negative view of Christianity present in Eastern cultures. He claimed that he was inspired by Francisco Goya’s “Peasant Before the Firing Squad”, adopting the stance of a person in despair with downward, outstretched palms (though, when actually looking at the painting, it seems more like the peasant has been turned upside down for Holtom’s symbol):
Even so, the peace sign has retained greater social recognition than Nero’s cross, though you will still find adamant Christians that shun Holtom’s peace sign, referring to it as a “broken cross”. I actually had a woodshop teacher back in middle school who wouldn’t allow me to paint a peace sign on my wooden plane for this reason.
Thus, the “broken cross”, as well as the inverted cross (which really shouldn’t be called “St. Peter’s Cross”, truthfully. It’s a nice story, and a nice thought, but there’s not much to substantiate it), has since been associated with a distinctly non-Christian attitude.
PEACE SYMBOL - Also known as the Cross of Nero. Many people are not aware of the origins of this symbol or how it became to symbolize peace. This is the cross of Nero, a broken and inverted cross, enclosed in a circle which represents Nero’s vision. Nero believed that there would be world peace without Christianity, thousands of Christians were martyred under the rule of Nero. This is what the “peace symbol” represents regardless of what it means to you.