Religious Tattoos

Before, when worship of the three fake Gods was still accepted, those under the worship of Tianya and R'holor would get a small black dot tattooed somewhere on their body. This was considered a very holy thing to do, and in some sense, it was akin to worship. It became a bit of a challenge put out to the worshipers of these Gods, the more publicly the dot is placed (other than the head/face, because the head is holy) such as lower arms or neck, the more holy the act was interpreted as. 
Once the worship of these Gods became illegal, people were left with these tattoo's symbolizing outlawed deities, and needed a way to get rid of them. While it is possible to get rid of them through magical needs, this is typically much rarer and more expensive than the tattoo itself. 
So, with the introduction of the new Gods, religious leaders made separate symbols to identify worship to these new Gods. People began getting these new additions to their tattoos, and soon enough, they became normal.