Many symbols in the New Testament recur again and again: bread, water, wine, rocks/pillars, etc. Fish are among the most common. Why, then, would Clement refer to pagan sources like Seleucus for a fish symbol instead of sourcing his suggestions to the New Testament itself? While he is clearly aware of the Bible stories, St. Clement seems to cite the “fishing” of the “apostle” in order to justify using the earlier pagan precedent.
To explain why the first Christians used symbols like a fish instead of the Cross, Christians often suggest that a secret symbol—a so-called “crux dissimulata”—had been necessary in the first centuries because Christians were being persecuted by the Roman Empire.
According to this explanation, Christians used the fish as a means of recognizing a fellow Christian by quickly scratching it into the sand without any fear of discovery by Roman authorities. And, certainly, Christians who refused to worship Roman state deities could be subject to criminal prosecution and even execution.
Yet, while it may have been convenient at certain times to have a secret code, it is not clear at all that pagans would have recognized the Cross as a Christian symbol during the first two centuries of Christian history. According to The Catholic Encyclopedia, not more than 20 examples have ever been found of the Cross being used as a Christian symbol during the entire first four centuries.
It would seem that an outsider would need the same knowledge of an insider to recognize a cross as a Christian symbol at all considering how rarely it was ever used. An outsider had a much better chance of recognizing a fish as a Christian symbol at this time since it was far more commonly used. How could the Cross be so recognizable during this period that disguising it would be necessary? And were these early Christians really in danger of discovery and persecution by the Roman government?
We now know much more about the treatment of Christians by the Roman Empire. Recent scholarship, such as that of Candida Moss, has revealed that traditional claims about Christian persecution have been greatly overstated. (25) The first Christian catacombs in Rome, dated to the early 2nd Century, were burial sites—not hiding places—just as the Jewish catacombs in Rome were before them. The symbols used by early Christians at their gravesites do not appear to have been any secret, but quite the opposite. They were used to identify the occupants as Christians. And the symbols they used most predominantly were fish and anchors, the same symbols stamped on the Emperor Titus’s coins.
We will take a close look at these earliest Christian symbols later. First, we need to consider why our modern understanding of Christianity’s origins makes it so difficult to believe that Romans, let alone Roman emperors, could be involved in the creation of Christianity. Our modern impression of persecuting Romans and oppressed Christians has built in a natural aversion to any such possibility.
Christians fed to lions, “The Triumph of Faith,” by 19th Century painter Eugene Thirion
The new discovery of this coin’s link to Christianity proves that within a decade or so of Flavian rule, starting in the early 2nd Century, Christians were publicly memorializing their faith on tombs, with no fear of imperial persecution, even as they used symbols associated with the emperor himself. And prominently buried in one of these tombs, indeed the oldest Christian catacombs, was the granddaughter/niece of three Flavian emperors. Today they are named after her (the Catacombs of St. Domitilla, although her remains were later moved to the basilica of Santi Nereo e Achilleo in Rome).
Facts like these already cast extreme doubt on the idea that Romans were persecuting Christians in the 1st Century. However, we know that some instances of Christian persecution by Roman authorities did in fact occur. According to our ancient sources, the late 3rd-4th Century Roman Emperor Diocletian and, later, Julian (the notorious “Apostate” from his family’s Christian faith) were explicitly and harshly anti-Christian emperors. Yet, before them, only Decius in 250 CE had enacted any law against Christians. And even under Diocletian, the evidence tells us that by the end of his second year of rule "the ferocity of the persecution [of Christians] had eased off again, and the earlier tradition of tolerance had begun to reassert itself.” (Emphasis added) (26)
More and more, the evidence suggests that the persecution of Christians was not at all common before the Christian faith started to become the official state religion of the Roman Empire under the Emperor Constantine in the 4th Century. By the reign of Emperor Gratian (359-383) paganism would be vigorously suppressed by the Roman Empire. There is simply no evidence that Christians were driven underground, as commonly depicted in movies and novels—at least not for any extended periods of time.
The first and only existing documentation of official Roman policy on Christians, dating prior to the brief reign of the hostile Emperor Decius, is this correspondence between Pliny the Younger, governor of the Roman province of Pontus-Bithynia (in modern-day Turkey), and the Emperor Trajan in 111 CE.
Pliny the Younger, façade of the Cathedral of St. Maria Maggiore
Pliny the Younger to Emperor Trajan:
It is my custom to refer all my difficulties to you, Sir, for no one is better able to resolve my doubts and to inform my ignorance.
I have never been present at an examination of Christians. Consequently, I do not know the nature or the extent of the punishments usually meted out to them, nor the grounds for starting an investigation and how far it should be pressed. Nor am I at all sure whether any distinction should be made between them on the grounds of age, or if young people and adults should be treated alike; whether a pardon ought to be granted to anyone retracting his beliefs, or if he has once professed Christianity, he shall gain nothing by renouncing it; and whether it is the mere name of Christian which is punishable, even if innocent of crime, or rather the crimes associated with the name.
For the moment this is the line that I have taken with all persons brought before me on the charge of being Christians. I have asked them in person if they are Christians, and if they admit it, I repeat the question a second and third time, with a warning of the punishment awaiting them. If they persist, I order them to be led away for punishment; for, whatever the nature of their admission, I am convinced that their stubbornness and unshakeable obstinacy ought not to go unpunished.
There have been others similarly fanatical who are Roman citizens. I have entered them on the list of persons to be sent to Rome for trial.
Now that I have begun to deal with this problem, as so often happens, the charges are becoming more widespread and increasing in variety. An anonymous pamphlet has been circulated which contains the names of a number of accused persons. Amongst these I consider that I should dismiss any who denied that they were or ever had been Christians when they had repeated after me a formula of invocation to the gods and had made offerings of wine and incense to your statue (which I had ordered to be brought into the court for this purpose along with the images of the gods), and furthermore had reviled the name of Christ: none of which things, I understand, any genuine Christian can be induced to do.
Others, whose names were given to me by an informer, first admitted the charge and then denied it; they said that they had ceased to be Christians two or more years previously, and some of them even twenty years ago. They all did reverence to your statue and the images of the gods in the same way as the others, and reviled the name of Christ. They also declared that the sum total of their guilt or error amounted to no more than this: they had met regularly before dawn on a fixed day to chant verses alternately amongst themselves in honor of Christ as if to a god, and also to bind themselves by oath, not for any criminal purpose, but to abstain from theft, robbery, and adultery, to commit no breach of trust and not to deny a deposit when called upon to restore it. After this ceremony it had been their custom to disperse and reassemble later to take food of an ordinary, harmless kind; but they had in fact given up this practice since my edict, issued on your instructions, which banned all political societies. This made me decide it was all the more necessary to extract the truth by torture from two slave-women, whom they call deaconesses. I found nothing but a degenerate sort of cult carried to extravagant lengths.