The outstanding unity of early Christian thought began to fade after the death of the apostles. From the second century, Greek philosophy and other pagan practices were mixing into accepted doctrine. From the Council of Nicaea, A.D. 325, Emperor Constantine’s fusion of the pagan religion of Rome with apostate Christianity moved ahead at a rapid pace.
In 378 A.D, Emperor Gratian granted Damasus, bishop of Rome, the right to bear the old religious title ‘Pontifex Maximus’. During his rule, much was done to embellish the catacombs beneath the city, the tombs of the martyrs. The former healthy Christian respect for the example of faith set by those who were martyred was now contaminated with the corrupt hero worship of Rome and turned into the saint worship of the following century..
With the catacombs cleaned up and adorned with more extensive inscriptions and artwork, they became shrines to which the people flocked, and the martyrs became the objects of worship. When Diocletian’s reign of terror was replaced by an era of toleration toward the Christians, they embraced both pagan thoughts and symbols. The simple clay lamps essential in the dark catacombs were now adorned with the zodiac pagan symbol of the fish.
Why a fish? Objects dated as far back as the second century C.E. have been found bearing this figure along with the Greek word for fish, ICHTHÝS. This is often taken as a cipher for the Greek expression ‘Iesous CHristos THeou Yios Soter’, meaning “Jesus Christ, Son of God, Saviour.”
According to The Interpreter’s Dictionary of the Bible, fish frequently, but not exclusively, appear in ancient pagan symbolism, often in a context quite apart from water scenes. “In such cases,” notes this reference work, “fish would seem to have symbolic significance, possibly to represent deity, power, fecundity, etc.”
Mons Perret, who spent fourteen years doing research in the catacombs of Rome, counted in all a total of 11,000 inscriptions among the millions of tombs. According to him, “Among the signs that appear are the dove, a symbol of the holy spirit; the lyre, a symbol of joy; the anchor, a symbol of hope and the fish”.
Furthermore, certain Jews adopted the use of the fish symbol from pagan religious sources. For example, the zodiac pisces, in the style of two circling fish, form part of the mosaic floor of the ancient Capernaum synagogue. “It is probable that these considerations account in part for the appearance of the fish in the art of the oldest Christian catacombs. How early the Greek word for ‘fish’ (ichthýs) came to be interpreted as a cipher for ‘Jesus Christ, Son of God, Saviour’ . . . we do not know; but once this identification was made, the fish became a standard Christian symbol.”
And so it is that the symbol of the fish, whether said to bear a new significance in the church or not, came to be a part of so-called Christian art in the catacombs, even as it had long been used by the pagans and seen in their places of burial. Some books dwell at length on the significance of this symbolism, but The Catholic Encyclopedia frankly admits that “writers have at times found a richer dogmatic content in the pictures of the catacombs than a strict examination is able to prove.” (Vol. 3, p. 423)
Although it has been noted that the catacombs provided places of refuge and assembly during times of persecution, it is now apparent that there was a return to the catacombs as places of worship when the persecution ended, but this time for a form of worship far removed from that practiced by the earlier Christians, a case could be made that the fish symbol in Christian use was Apostate Christian use.
Certain groups make much of the so-called astrological ages. Some two thousand years ago, the sun moved from Aries to Pisces. This accounts for one so-called link between the birth of Christ and the Age of Pisces, or the fishes. There is no scriptural basis for such a link, which is without doubt both approximate, and coincidental, but rather Astrology is expressly condemned in the Bible. Interestingly, the signs of the zodiac, including Pisces, found their way into such places as the Cathedral of Notre Dame in Paris, as well as the cathedrals of Amiens and Chartres, France.