The ichthys or ichthus, from the Greek (fish), is a symbol consisting of two intersecting arcs, the ends of the right side extending beyond the meeting point so as to resemble the profile of a fish. It was used byearly Ghristians as a secret Christian symbol and now known colloquially as the "sign of the fish" or the "Jesus fish"

What is the origin of the Christian fish symbol?

The Greek word for fish is "ichthys." As early as the first century, Christians made an acrostic from this word: Iesous Christos Theou Yios Soter, i.e. Jesus Christ, Son of God, Savior. The fish has plenty of other theological overtones as well, for Christ fed the 5,000 with 2 fishes and 5 loaves (a meal recapitulated in Christian love-feasts) and called his disciples "fishers of men." Water baptism, practiced by immersion in the early church, created a parallel between fish and converts. Second-century theologian Tertullian put it this way: "we, little fishes, after the image of our Ichthys, Jesus Christ, are born in the water."
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