I am not sure if having a tattoo with a cross or an angel would let the person of faith in inside the church to attend mass. I have witnessed a well-dressed couple and the woman had a tattoo of satan on her right calf. I didn't like the motive myself for her coming in to hear mass showing her tattoo like that, it could have been covered with pants. A church volunteer immediately spotted the unwelcome mark on her leg and asked her politely to leave the church.
As a Catholic, a tattoo of a cross or angel indicates that I admire and believe in those symbols. But I truly feel that it is not appropriate to show it off depending on a piece of clothing the bearer is wearing that exposes it; if this person is going to church, attending weddings, or any other religious affairs. I guess it would be the same for exposing ANY obvious tattoo and not limited to religious tattoo symbols.
The church asks people to dress appropriately out of respect, what more with ink marks on our body?
That's a good question you have, thelyricwriter!