A discussion of the question which is often cited these days is pp. 24-26 of Graydon F. Snyder's useful compendium Ante Pacem: Archaeological Evidence of Church Life before Constantine (Mercer Univ. Press, 1985).
Clement Paidagogos 3.11: "Let our seals be the dove, or the fish, or a ship sailing before the wind, or the lyre for music, which seal Polycrates used, or a ship's anchor, which Seleucus carved on his device, and if there be a fisherman, he will recall an apostle and children drawn from the water.".
Tertullian in the 1st chap. of De baptismo: "But we little fish, according to our ichthyn Jesus Christ, are born in the water, nor are we saved in any other manner than by remaining in the water."
David Lupher
Classics Program
Univ. of Puget Sound
It is true that the birth of Jesus, and the advent of Christianity in general, has long been associated with the astrological "Age of Pisces," that is, the period of time in which the synodic vernal point makes its slow retrograde transit through the sign of Pisces. [This is due to the precession of the equinoxes, and the synodic vernal point is the intersection of the ecliptic with the terrestrial equator]. The SVP changes one degree about every 72.5 years, making one astrological "age" about 2175 years long; I do not know, however, whether the actual ingress of the SVP into Pisces occurred precisely in AD 1. I rather suspect it didn't.
By the way, in astrological symbolism, there are very profound and somewhat complex associations of the sign Pisces with Jesus Christ and Christianity, although I can't really tell the chicken from the egg without further research. I do know that modern interpreters of the astrological "ages" point out that the Age of Aries, which preceded the Age of Pisces wherein we are now situated, culminated in the expansion of the Roman Empire, the connection being the association between Mars (god and planet) and the symbolism of Aries. Furthermore, the Age of Taurus (one more age previous) is associated with Minoan civilization, pointing to cults associated with the sacred Bull, the Age of Gemini is associated with the proliferation of writing and sea-faring, and the Age of Cancer is associated with pre-historical matriarchal societies (Cancer is a sign with strong maternal associations).
Philip Covitz
Rhetoric Dept.
UC Berkeley
Danielou and Snyder are both very useful on fish and other symbolism, but a little out of date. I happen to be working on this very topic at the moment, so I've been interested in the discussion so far. The most recent pronouncement on the use of the fish symbol in early Christianity that I know of is:
G. Stroumsa, "The Early Christian Fish Symbol Reconsidered," in Messiah and Christos: Studies in the Jewish Origins of Christianity, I. Gruenwald, S. Shaked & G. Stroumsa edd (Tubingen: Mohr, 1992): 199-205
The article includes a review of the secondary literature on this subject to date and argues for an origin of the symbol in Judaism (pace Goodenough and Scheftelowitz).
In my own investigations (yet to be completed), I can find no clear evidence for the use of the IXTHUS acronym in early Christianity much before the late second century AD. There is lots about fish and fishermen in the New Testament, of course (much more than in the Old Testament, incidentally), but the earliest known reference in Christian literature is, as list members have already observed, in Tertullian, De Baptismo 1.3, where the word for fish is written in Greek instead of Latin and so alludes probably to the acronym IXTHUS to which list members have also referred. The acronym and fish symbols are found in tombs now buried beneath the church of San Sebastiano, Rome, but, while highly likely, it's not universally accepted that these tombs are Christian. At any rate, they date from the late second/early third century as well. The acronym is clearly in use by the fourth century AD, and Augustine tells us that it means "Christ" ("Jesus Christ, Saviour, of God the Son, Saviour", spelt out in Greek), as pointed out by list members, because, as Augustine says "He was able to remain alive - that is, without sin - in the abyss of our mortal condition, in the depths, as it were, of the sea" (City of God 18.23, part of a discussion of Sibylline Oracle 8.217). These baptismal associations may have been reinforced by the happenstance that at the time the baptismal font could be referred to as a "piscina".
The acronym seems to lie behind a passage in the epitaph of Abercius, an enigmatic Phrygian inscription, now in the Vatican, which probably dates from the late second century. The inscription is in Greek, though, so it's hard to tell:
My name is Abercius, the disciple of the Holy Shepherd ...I followed Paul and everywhere Faith was my leader and she gave me food in every place - the Fish from the fountain, a mighty Fish and pure which a holy maiden took in her hands and gave to her friends to eat for ever, having goodly wine and giving it mixed with water and also bread...Similar language is used in the inscription of Pectorius, which was found near Autun and kept in the museum there. It has not been securely dated - I suspect it's fourth century. This inscription is also in Greek, but it's written in verse (of a sort) and the first letters of the first five lines spell out IXTHUS:
Divine race of the heavenly Fish preserve a reverent mind when thou takest of the immortal fountain of wondrous waters that springs up among men. Friend, let thy soul be comforted with the ever-flowing waters of wealth-giving wisdom. Take the honey-sweet food of the Saviour of the saints and eat it eagerly, holding the Fish in thy hands. Satisfy me with the Fish I pray thee, My Lord and Saviour....be mindful of thy Pectorius abiding in the peace of the Fish.Fish imagery generally is popular in early Christianity, and crops up in patristic literature. Clement of Alexandria sanctions the use of the image in art in Paedogogus 3.11. Fish and anchors are drawn alongside funerary inscriptions datable at the earliest to the late second/early third centuries, a few of which have been accepted as Christian. Fish imagery that may date from this period also occurs in the catacombs, the best known example being the so-called "Eucharist fish" with a basket of bread in the Lucina crypt in the Catacomb of Callixtus, Rome.
Goodenough ("Jewish Symbols"), in his discussion of fish symbolism, points out that there were various astrological motifs on the ceiling of the synagogue at Dura Europos, and these include the symbol for Pisces. Datable probably to the late second/early third centuries again - certainly no later than 256 AD, when the town was destroyed and abandoned. Astrological imagery is prevalent in both Judaism and Mithraism during the third and fourth centuries - I'm not sure that it's all that common in Christianity but maybe this just hasn't been investigated. I'll certainly be watching out for it now.
Gail Tatham
Dept of Classics
University of Otago