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Ichthys as a Christian symbol
An early circular ichthys symbol, created by combining the Greek letters ΙΧΘΥΣ, Ephesus.
The use of the Ichthys symbol by early Christians appears to date from the end of the 1st century AD. Ichthus (ΙΧΘΥΣ, Greek for fish) is an acronym, a word formed from the first letters of several words. It compiles to "Jesus Christ God's Son Saviour", in ancient Greek "Ἰησοῦς Χριστός, Θεοῦ Υἱός, Σωτήρ" [Iēsous Christos Theou Yios, Sōtēr].
Iota is the first letter of Iesous (Ἰησοῦς), Greek for Jesus.
Chi is the first letter of Christos (Χριστóς), Greek for "anointed".
Theta is the first letter of Theou (Θεοῦ), that means "of God", genitive case of Θεóς "God".
Upsilon is the first letter of Huios (Υἱός), Greek for Son.
Sigma is the first letter of Soter (Σωτήρ), Greek for Saviour.
Historically, twentieth century use of the ichthys motif is an adaptation based on an Early Christian symbol which included a small cross for the eye or the Greek letters "ΙΧΘΥΣ". Catholic theology has elaborated on the five words of the acronym into the "Jesus prayer", or, "Lord Jesus Christ, Son of God, have mercy on me, a sinner."
An ancient adaptation of ichthus is a wheel which contains the letters ΙΧΘΥΣ superimposed such that the result resembles an eight-spoked wheel.
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The Christian Fish Symbol (also called 'The Jesus Fish')
Christian fish symbol
The Christian fish symbol is usually just two simple curved lines. Modern looking and sleek, often seen on car bumpers, it gives many people the impression that it's a new symbol. In fact, its history goes back even further than the cross as a symbol used by Christians.
As early as the second century Titus Flavius Clemens (St. Clement of Alexandria), suggested that Christians identify themselves with a seal engraved with a fish or dove (see also Dove Cross). The fish in particular, was considered important enough to be mentioned many times in the Bible. Clemens was a Greek theologian and noted that letters of the Greek word for fish, ΙΧΘΥΣ (pronounced Ichthys), made the following neat little acrostic:
Iesous Christos Theou Yios * Soter
Jesus Christ God's Son Saviour
(* pronounced Iios -
with emphasis on the 'o')
At this time, the cross was not used as a Christian symbol, so the fish gave them something simple and easily recognisable, plus a motto that described their Jesus as Christ, God's Son, and Saviour. (This idea might have also been partly a protest against the Pagan emperors of the time, who named themselves Theou Yios: God's sons).
The lowercase Greek character for Alpha (α) is similar to the fish symbol. This may also have had some influence on the decision for Christians to adopt the symbol, since Jesus calls himself "the Alpha and the Omega"1 – the beginning and the end. (See also Alpha and Omega Cross.)
In the fourth century, the cross became a more popular symbol for Christians, and the symbolism of the fish gradually disappeared.
In recent years, some Christian groups have attempted to give their religion a fresh new look by reviving the fish as an alternative symbol. Some argue that this is a healthy 'downgrading' of the cross, which is simply a symbol of Christ's crucifixion and resurrection. The cross, they say, should not be treated as a god (being mindful not to revere the fish symbol2). Other groups prefer the cross, because the fish symbol doesn't reflect Christ's sacrifice. Fortunately for Christians, they can make their own choices. (See also Jesus Fish Cross and Fish Hook Cross.)