Your question comes at a time when many people are asking about the appropriateness of tatoos. Parents, especially, are facing the increasing number of adolescents who want to have this form of “body art” displayed on their torsos. There is nothing inherently sinful about tatoos. I have researched the topic to find out what the Church’s teaching might be and have found no definitive answer. We are left, then, when trying to establish a reasonable response to the question.
It is certainly true that many people consider excessive tatoos to be wierd and disgusting, especially those which cover 50-90 percent of the whole body. There is a reference in Leviticus 19: 28 that says, along with a number of other prohibitions, “you are not to tatoo yourselves.” That is the only place in scripture which mentions the subject. It was part of many prohibitions given to Moses and it is likely mentioned because tatoos are images and the Israelites were forbidden either to make or worship images because pagans did so as objects of worship.
The best answer to your question lies in the belief of Christians that our bodies are “temples of the Holy Spirit,” and are thus sacred. Bodies must be objects of respect and many tatoos display holy images, along with other more profane art, and the danger is to see these as trivializing what is sacred.
The Hebrew scriptures do issue warnings against “mutilation” but tatoos are not considered such. Mutilation involves cutting or maiming a part of the body. There was an ancient superstition, of which the Israelites were aware, that pagans practiced . This was for a family member to tatoo the body of the deceased with fearful images in order to scare off evil spirits. This was part of a whole body of superstitions which existed at the time and the Church has always warned against a faith infused with superstitious beliefs.
The deeper questions is “do tatoos dishonor or disfigure the body?” Do they reflect our respect for the body as a spiritual temple? Does it add to the dignity of the body? At a time of rampant exploitation of the human body through pornography, explicit sexual references in advertising, and pornographic art, it is important to resist anything which might denigrate the body. We have all seen tatoos on men, especially, which displays vivid images of Christ or the Virgin Mary or crosses intermingled with hearts and sexy looking women. Tatoos among women are becoming increasingly popular but they tend to be more smaller and more subtle and less dominantly displayed. There is a growing body of opinion that sees tatoos simply as “body art,” and that people have a right to express themselves. Some tatoos are on parts of the body that are not visible except when either scantily clad or naked. Some are rather neutral: a family shield, a shamrock, a small heart, a small American flag, a tiny cross etc. One needs to remember, too, that tatoos are permanent(or at least painful and expensive to remove). Be careful what you inscribe on your skin; these images will be permanent companions for the rest of your life. The values of an adolescent might change with maturity and age!
I would be hesitant to make any definitive statement about the sinfulness of tatoos. I do see massive covering of the body with tatoos as denigrating the sacredness of the human body. When tatoos display symbols of hatred, such as swastikas, or any other image associated with violence and prejudice against others, that is sinful. If a tatoo glorifies violence or denigrates another’s religion, that is sinful. Many religions might consider casual display of symbols, like Stars of David, Crosses, Buddhas, Crescents etc. a sinful use of the sacred. The glorification of sex on a person’s body would be unacceptable to most people of faith. They may also lead to scandal, which is any act which might lead people into sinful behaviour. Some tatoo art might be considered immodest in certain societies. But we must be careful not to judge others. When a Catholic, or other Christians, ponder over whether to walk into that tatoo shop, he or she is invited by our Christian sense of virtue, modesty, love and peace, to carefully decide what will either enhance or detract from our bodies as “temples of the Holy Spirit.”