It probably wasn't most brilliant idea I ever came up with to get a tattoo in college (junior year, March 12, 1993 to be exact), but at least it was a Trinity symbol. I had been thinking of getting a tattoo for a while, I just didn't know what to get done. When I saw the triangle of three fish embroidered on a kneeler pad in Cleveland, OH, I knew that was it. Before it registered in my mind that I was a paying customer and could make the artist change the design (even if he was big and scary-looking), "Ace" was already working on the outline, which is well...permanent*.
In Baptism, we are marked with the sign of the Cross on our forehead and on our heart to identify us as one redeemed by Christ, the crucified, who bears the marks of our sin in His own body. We remember that Baptismal mark every time we make the sign of the Cross. That cross from our Baptism is invisible - but it's just as permanent as a tattoo, if not moreso. It marks us in this life...and marks us for eternal life in Jesus Christ.