The Church certainly teaches against any form of self-mutilation and encourages modesty; there are no specific teachings against tattoos. It would depend upon the purpose, size, content, location. I have seen a few tattoos that are spiritually beautifully ~ however I they have been in the minority. Most of them are not…and many of the ladies have them in rather immodest places. Can we justify the entire industry for the handful of “appropriate” tattoos that are out there?
Leviticus 19:28: “You shall not make any cuttings in your flesh on account of the dead or tattoo any marks upon you: I am the LORD.”
Corinthians 6:19 Do you not know that your body is a temple of the Holy Spirit within you, which you have from God? You are not your own; 6:20 you were bought with a price. So glorify God in your body.
A tattoo is an unnecessary, permanent modification of the body given to us by God, which has been sanctified to be made a Temple of the Holy Spirit, through baptism. That, in itself, would argue against tattoos, not to mention the fact that many are contrary to Christianity and nature itself, and many are immodest, in form and location.
The Catechism of the Catholic Church in paragraph #2297 teaches that “Except when performed for strictly therapeutic medical reasons, directly intended amputations, mutilations, and sterilizations performed on innocent persons are against the moral law”.
To the degree that tattoos are body mutilations, they should be avoided. All people have an obligation to keep there body healthy. Tattooing and excessive piercing expose the body to needless infection.
Please read this pamphlet on the subject by Catholics United for the Faith.