Ichthys

The ichthys, also spelled ichthus, comes from the ancient Greek ΙΧΘΥΣ or ἰχθύς, meaning "fish." In its modern form, the symbol is made of two intersecting arcs, with the right ends extending past the meeting point to create the outline of a fish. Today, it is commonly called the "Jesus fish" and is used by Christians as a sign of their faith, appearing on vehicles, necklaces, and laptop stickers.

The symbol first appeared in Christian art and literature in the 2nd century. Its use among Christians became popular by the late 2nd century and spread widely in the 3rd and 4th centuries. Early Christians held the ichthys in "the most sacred significance." Some claim it was used to recognize churches and fellow believers during times of persecution in the Roman Empire. Church Father Augustine wrote that the fish symbolized Jesus well, noting that "he was able to live [...] without sin in the abyss of this mortality as in the depth of waters." The symbol also references the sacraments of Baptism and Communion. Regarding baptism, Tertullian taught that just as water sustains fish, "We, little fishes, after the image of our Ichthys, Jesus Christ, are born in the water." For the Eucharist, the miracle of the multiplication of loaves and fishes had close connection in both time and significance. The ichthys appears in the Catacombs of Saint Sebastian and the Catacomb of Priscilla, and is mentioned in the 1st–2nd century Latin text *Oracula Sibillina*.

The Greek letters ΙΧΘΥΣ form an acronym for "Ἰησοῦς Χρῑστός Θεοῦ Υἱός Σωτήρ," meaning "Jesus Christ, God's Son, Savior." A 4th-century adaptation superimposes these letters to create a shape like an eight-spoked wheel, though some propose this round symbol represents a loaf of bread.

Fish appear with symbolic meaning several times in the Gospels. Several of Jesus' 12 Apostles were fishermen, and he told them, "I will make you fishers of men" (Mark 1:16–18). After his resurrection, Jesus ate grilled fish (Luke 24:41–43). At the feeding of the five thousand, a boy brought "five small loaves and two fish," which Jesus multiplied. In Matthew 13:47–50, the Parable of Drawing in the Net compares angels sorting the righteous from the wicked to fishers keeping good fish and throwing away bad ones. In John 21:11, the disciples caught 153 fish after Jesus told them to cast their nets on the other side; Jesus then cooked fish for them. In Matthew 17:24–27, Jesus told Peter to find a coin in a fish's mouth to pay the temple tax. The fish also symbolizes the "Sign of Jonah" (Matthew 12:38–45), pointing to Jesus's resurrection, the foundation of Christian faith (1 Corinthians 15:1–58).

According to tradition, early Christians under Roman persecution used the fish symbol to mark meeting places and tombs, or to distinguish friends from foes. One ancient story says that when a Christian met a stranger on the road, they might draw one arc of the fish in the dirt; if the stranger drew the other arc, both knew they were believers. This practice is echoed in modern bumper-sticker and business-card uses. Other hypotheses for the fish's choice exist. Some sources note that Clement of Alexandria recommended his readers engrave their seals with a dove or fish (*Paedagogus*, III, xi). However, Roman monumental evidence from the Cappella Greca and Sacrament Chapels of the catacomb of St. Callistus suggests the fish was known to Christians much earlier.

In the 1970s, the "Jesus Fish" gained popularity as an icon of Christianity. In 1973, the symbol and its message appeared at the Aquarius Rock Festival in Nimbin, Australia. Today, it is seen as a decal or emblem on car rear ends, or as pendants and necklaces, signifying the owner is Christian. These are often given away or sold at Christian religious goods stores. Versions include an ichthys with "Jesus" or "ΙΧΘΥΣ" inside, or just the outline. One writer noted that while many Christians hang a cross or rosary inside their vehicles, "the fish sticker on the car is a more conscious symbol of a witnessing Christian—significantly, unlike the former, it is on the outside of the car for everyone to see." The Ichthus Music Festival, an annual large outdoor Christian music festival in Wilmore, Kentucky, started in 1970 and is the oldest such festival in the United States.

The idea that the ichthys was used as a secret symbol is based on an argument from silence by Robert Mowat.