The Fish: An Ancient Christian Symbol

Copyright © 2003, 2006, 2008 by Larry G. Overton

IxthusDecals and bumperstickers sporting the symbol of the fish are seen on cars all the time. In some cases, the mere outline of a fish is all that is displayed. In other cases, the outline of the fish has a cross inside of it, strategically placed so as to resemble the eye of the fish (I call this one the “cross-eyed fish”). In still other cases, the outline of the fish encloses a written word: either the name “Jesus” or the Greek word ΙΧΘΥΣ. (We’ll talk more about that Greek word in just a moment.)

So what does this fish symbol mean? How did the use of the outline of a fish come to be a Christian symbol? Is it Scriptural? Answering these questions is what this Berean Fact Sheet is all about.

What Does It Mean?

The fish symbol is used to represent Jesus Christ. To discover why, we must now discuss that Greek word I mentioned earlier: ΙΧΘΥΣ (pronounced ich-thys). And the word, as you may have already guessed, means “fish.” The form ΙΧΘΥΣ is written in all uncial (i.e., capital) letters. Written in minuscule letters, it would look like this: ἰχθύς.

This Greek word for “fish” is used as an ancient acronym, a word “formed from the initial letter of each of the successive parts of a compound term.” For a modern example of an acronym, consider the word “radar” (radio detecting and ranging). In the case of the word ΙΧΘΥΣ, it was and is used as an acronym for Ἰησοῦς Χριστὸς Θεοῦ Υιὸς Σωτήρ, which means, “Jesus Christ, God’s Son, Savior.” (For more detailed information on the preceding Greek phrase, see the following table.)

Name of Greek Letter English Equivalent Greek Word Represented Greek Word Transliterated Greek Word Pronounced English Translation
Ι (Iota) Ι Ἰησοῦς Iēsous Yee-soos Jesus
Χ (Chi) Ch Χριστὸς Christos Chrees-tos Christ
Θ (Theta) Th Θεοῦ Theou Theh-oo God’s
Υ (Upsilon) U (or Y) Υιὸς Uios Hee-os Son
Σ (Sigma) S Σωτήρ Sōtēr Sow-teer Savior

How Did It Start?

Exactly how and when the fish began to be used as a Christian symbol is difficult to say. We know this, however: the practice is very old. The fish was found as a symbol in the Catacombs at Rome. The first dated one belongs to the year AD 234 (the so-called “Eucharist fish” with a basket of bread in the Lucina crypt in the Catacomb of Callixtus, Rome). The earliest literary reference to the use of the fish as a Christian symbol is probably a reference in Tertullian’s De Baptismo (“On Baptism”), Chapter I, written before the turn of the third century AD (c. 193).

But we, little fishes, after the example of our ΙΧΘΥΣ Jesus Christ, are born in water, nor have we safety in any other way than by permanently abiding in water…

The significant thing about Tertullian’s reference is that he wrote in Latin…that is, until he came to the word ΙΧΘΥΣ. At that point, he switched to Greek. Clearly, he expected his readers to understand his reference. He assumed the use of the fish as a symbol of Christ to be widespread. Another literary reference to the use of the fish as a Christian symbol appears in Clement of Alexandria’s Pædogogus (“The Tutor” or “The Instructor”), Book III, Chapter 11, written around the year 202 AD. In this reference, Clement sanctioned the use of the fish as a symbol for the seal of a signet ring.

Two hundred years later, Augustine of Hippo wrote concerning the ICQUS acronym in his De Civitate Dei or The City of God (Book XVIII, Chapter 23).

But if you join the initial letters of these five Greek words, Ἰησοῦς Χριστὸς Θεοῦ Υιὸς Σωτήρ, which mean, “Jesus Christ the Son of God, the Saviour,” they will make the word ἰχθύς, that is, “fish,” in which word Christ is mystically understood, because He was able to live, that is, to exist, without sin in the abyss of this mortality as in the depth of waters.

Regarding this comment by Augustine, there can be no doubt that the ΙΧΘΥΣ acronym was known in the early fifth century AD (Augustine completed The City of God in 426 AD). It is significant too that he, like Tertullian before him, wrote in Latin and switched languages when referring to “these five Greek words” [Ἰησοῦς Χριστὸς Θεοῦ Υιὸς Σωτήρ] and to the word ichthys [ἰχθύς].

Is It Scriptural?

This ΙΧΘΥΣ acronym is not spelled out and explained in some passage of Scripture in the Greek New Testament. However, the meaning of this Greek acronym is most definitely Scriptural. It is said that the fish became a Christian symbol because of several of the apostles being fishermen, and because Jesus said to them, “Follow me, and I will make you fishers of men.” (Matthew 4:19; Mark 1:17)

Furthermore, the theological statement behind the ΙΧΘΥΣ acronym is also thoroughly Scriptural. In the first verse of his Gospel, Mark speaks of the beginning of the good news “of Jesus Christ the Son of God” (Greek, Iēsou Christou uiou tou Theou [Ἰησοῦ Χριστοῦ υἱοῦ τοῦ Θεοῦ]). The announcement to the shepherds in Luke 2:11 was, “For to you is born this day, in the city of David, a Savior, who is Christ the Lord.” The Greek word used for “Savior” is Sōtēr [Σωτήρ].

Therefore, while the acronym itself may not date from New Testament times, its meaning is Scriptural. And the evidence shows that: it developed soon after the first century; that it was known at the end of the second century; and that it was well established by the early fifth century. Christians today may therefore use it with confidence in their statement of faith in Jesus of Nazareth as the Anointed One (or “Christ”), the Son of God and our Savior.