Q. What does the fish with letters inside mean? Where did it come from and what makes it a Christian symbol?
A. The symbol consists of a fish with five letters from the Greek alphabet, IXOYE , which spell the Greek word for fish. (In English they’re pronounced I-ch-th-y-s.) They are also the first letters of five Greek words: Iesous Christos Theou Yios Soter. In English this means ‘Jesus Christ, God’s Son, Savior.’
In the early days of the Church, the practice of Christianity was a serious crime in the Roman Empire as well as in Israel. Jesus said the time would come when people would think they were performing a service to God by killing His followers (John 16:2)
To protect themselves, Christians would mark the entrance to meeting places with the symbol of a fish to show other Christians it was safe to come in and join them. The five letters were added later.
I’ve been told that believers are still using secret ways of identifying themselves to each other in countries where Christianity is illegal. Some say that during the end times all believers in Jesus will have to resort to such things to protect themselves against the likelihood of betrayal.
If you live in a country where the public practice of Christianity is permitted, then you have one more thing to be thankful for today. You should take advantage of your freedom while you still have it. And you should offer prayers of protection over those who risk their lives every time they say the name of Jesus.