Why is the FISH a symbol of Christianity?

Before I answer this question let me say that I've always wished to swim with dolphins. But I couldn't afford such a holiday so I went swimming with sardines instead.

Now sardines are not as clever as dolphins. Why else would they get into a tin and leave the key on the outside?

Every other canned fish you buy, tuna, salmon, pilchard and so on, you have to open with a can opener. But sardines ... they have a key on the outside. Why?

Unless of course you buy those tins with a ring pull. Again, on the outside ... so the sardines can't pull the ring and get out.

Anchovies thought they'd be clever by being so salty that no one would eat them. They were wrong. They've now become a delicacy much sought after and fished than before.

And now about the original question ...

The symbol of a fish was found on ancient Christian monuments and buildings. It represents Christ.

The Greek word for "fish" is ICHTHUS.

If we take the letters of that word they provide the first letters of other Greek words.

Iesous Christos Theou Uios Soter

Jesus Christ, Son of God, Saviour

So the symbol of the fish suggests all this to a Christian. It may well have been a secret sign used by early Christians to identify each other.