Tilapia has been around since 1500 B.C. ~ it's not surprising then that the fish has history connected to the Bible. It has been fished in the Sea of Galilee for thousands of years.
Supposedly the fish that was caught by St. Peter was thought to have been tilapia. This is one reason why the fish is also known as "St. Peter's fish" and is separated from meat according to Lenten standards.
Here's why most cooks like tilapia: it's inexpensive, easy to prepare, widely available and "goes with everything." It's also a good source of protein and has a low to moderate fat content. It tastes pretty good too.