Flung to the lions?

Nero, according to the Roman historian Tacitus, blamed the conflagration in Rome on a small, obscure sect: the Christians. Tacitus, who disliked emperors, later exonerated the Christians. Paul the apostle was probably in Rome about the time Nero was emperor.

Nero had some Christians crucified, while others he had strait-jacketed, daubed with pitch and made into human torches in his garden (the Vatican). Still others were dressed in the skins of wild animals and exposed to packs of rapacious wild dogs and eaten alive for the entertainment of the arena crowds.

Ca. 300 B.C., Diocletian conducted a vicious pogrom against Christians.

Source: "Paul: The Mind of the Apostle" by A.N. Wilson

The Book of Revelation gives the number of the beast as 666, which, among other things, represents the name Neron Caesar. This observation is long-established and noncontroversial. However, such numerology can almost always be applied to more than one name. Yet, the use of a number may imply that the author of the book had reason to fear use of the name. He says, "let the reader understand." (The true author of most of the book is Jesus, according to the account given in Revelation.)

I found this on the internet, and it seems reasonable:

The Romans did throw people to lions on occasion, and Tertullian, writing later, remarks that the Romans were always ready to exclaim "Away with the Christians to the lion!" whenever times got tough. However, Tertullian doesn't claim he witnessed any martyrdoms-by-lion personally, and anyway he was a Christian himself. Fact is, while the Romans evidently fed Christians to animals, and people to lions, we have no source stating directly that they specifically fed Christians to lions.

"To the lions" might stand for "to the beasts," the latter being a specific Roman death sentence. Beasts included dogs, bears and lions. I would imagine that lions were rather difficult to handle and so breaking them out for the masses might be a rare "treat."

Now the fact that Roman popes were responsible for decidedly un-Christian massacres of dissidents might be seen in light of the fact that these pontiffs were usually worldly men of great political power. Curiously, the "donation of Constantine" which granted the popes worldly power turned out to be a forgery. In that document, the phrase "vicar of Christ" is found, and a numerological analysis comes up with 666.

Otherwise, that title is apparently not found for popes.