Just because history does not record something does not mean such a practice did not happen in the ancient past. As far as we know it appears to be a recent thing, but even the idea of the supposed story of Peter being crucified upside down is not a good one to imitate because Peter is not our Lord and Savior and it was making a mockery of the cross upon which Jesus died. What is odd is that the Catholic church at one time condemned a man who was using the cross in an upside down way.
Here is a quote from another poster on another Christian Forum:
Eugène Vintras (1807–1875) may be the first to use the inverted cross in a distinctly anti-Christian way. He was a Gnostic revivalist operating in France during the middle of the 19th century. He preached the end of the age, and claimed to have received messages from Michael the Archangel and that he himself was a reincarnation of Elijah. He was condemned by the Vatican, and subsequently began using an upside-down cross:
Vintras, following further attacks from the Church, adopted the inverted cross as the symbol of the new dispensation of which he was the prophet, inverted because the Reign of the Suffering Christ had been superseded by the Reign of the Holy Spirit of Love.
His masses reportedly included "chalices magically overflowing with blood," and occultist
Eliphas Levi considered the inverted cross that Vintras wore as "indicative of satanic influences"
Source:
When did the "upside down cross" become a symbol of anti-Christianity?
This suggests that the Catholics were not using the upside cross prior to this event and they also have taken on this upside down cross recently, as well. They simply could have added to their history books that they had always did this. For just because something is reported to be written in history, does not always mean that it is true. For let God be true and let every man be a liar.
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