Following on from my friend, Deacon Lawrence's excellent discussion of nudity in Christian art, here is a different, but complementary argument that supports his assertion that it is appropriate, but only in certain circumstances. What follows is a summary of a longer article published some time ago in a Festschrift for my friend Stratford Caldecott, which you can download here. 

When Pope John Paul II presented his Theology of the Body and addressed artists directly, he challenged them to portray the human figure 'naked without shame' and in such a way that the beauty of the human form would be revealed in an ordered way. He reiterated this at he re-opening of the Sistine Chapel after its cleaning and restoration in 1994.This caused quite a stir at the time. Here was a respected Pope (now Saint) who was putting his intellectual weight behind the artistic tradition of painting the nude...and not only excusing it but promoting it!Many cultured and arty Catholics in the chattering classes heaved a sigh of relief. Now they could point to the words of the Pope and claim that they were right at the cutting edge of culture and simultaneously in the mainstream of the Church! Now they were as free to air their views over coffee after Mass as they were with their secular friends at dinner parties, for the Pope, no less, had become an apologist for the Sixties. After all, he was telling the Philistines who were uncomfortable with nudity that they didn't really understand Catholic culture. Many artists didn't miss the point either. The Pope's challenge to them inaugurated the creation of a wave of contorted Theology-of-the-Body nudes that, the artists told us, communicated human sexuality 'as a gift' through the exaggerated gesture of intertwining limbs and torsos.

I accepted this view too, to a degree. Then I actually read the Theology of the Body and John Paul II's address on the re-opening of the Sistine Chapel.

When several years ago I moved to the US from the UK and started teaching at a Catholic college, I knew that I would have to deal with parents who were devout Catholics who might be hesitant about allowing their sons and daughters to draw nudes in figure-drawing classes. I imagined that they would have been even more nervous about the idea of some of them posing for the classes.

In order to have some good Catholic arguments to persuade them of the appropriateness of this, I set about looking at the tradition of the nude in Catholic art as well as reading the Holy Father's words on the subjects.

I was surprised by what I came up with. Rather than finding evidence to bolster my view. I found the reverse. I had to abandon certain assumptions that I had held until that point and made me reconsider my position altogether. 

• It is not necessary to study the nude to draw or paint the human person, even in naturalistic styles well.
• The Christian tradition is very cautious about nudity in art and for most part avoids it. The nude appears consistently in the tradition only a very limited way and in connection with certain subjects (eg Genesis and the account of the Fall) where it is crucial to understanding the passages. It has to be in accord with compositional and stylistic considerations that maintain the dignity of the person portrayed. 
• The artist has to take into account the sensibilities of the time and these can vary. The artist must always avoid lasciviousness, but what that means precisely is going to be different at different times.
• John Paul II himself was, consistent with tradition, extremely cautious about the portrayal of the nude. He most certainly was not promoting in any way of the liberal attitudes of the 20th century. He advocated that naturalistic styles of art should not portray the nude. 

When I read John Paul II's writing referred to above, and his Letter to Artists of 1999, what I see is someone who understands and respects the differing traditions in art very deeply and who is conservative by nature. Far from giving models carte blanche to take their clothes off, and voyeuristic artists his blessing to paint them. He was in fact, in accordance with Catholic tradition, strongly against the portrayal of the nude in both the grotesquely distorted and erotic modern styles and the style 19th-century realists.

In fact he said that the human person should only be portrayed nude only we see the body is shining with the 'light that comes from God'. This narrows the scope  indeed. It is a reference to what in the context of traditional iconography is called the 'uncreated light' of sanctity. He is proposing that only highly idealised representations of the human form are appropriate for the nude. While this doesn't rule out new interpretations consistent with the principle, historically, it is the highly stylized iconographic

or gothic forms that incorporate this systematically.

In common with other Christian commentators he also sees great dignity in the nudes of ancient Greece.

It is the correspondence to this idealised form, and not its naturalism I suggest, that causes him to appreciate the work of Michelangelo so highly, especially his frescoes in the Sistine Chapel.

William Blake is another artist whose style is obviously related to the ancient Greek ideal (thank you to Bill Donaghy for pointing this out to me).

Rather than blandly stating the human body is beautiful and so always appropriate for nudity, we must recognise that man after Fall, which is who we are, is not shining with light in the same way, and also is prone to look with impurity at other. With this in mind, the way to restore man after the Fall, which John Paul II called Historical Man (ie all of us now ) to the dignity of Original Man (man before the Fall) whether in art or in reality is the same, put some clothes on, for heaven's sake!

Clothes on fallen man, don't hide the beauty of the body, they complete it in a dignified way. That is why, incidentally it is traditional to have masculine and feminine clothes - so that human sexuality can be revealed in an ordered way. To put it bluntly, before the Fall, man was clothed in glory; after the Fall, man retains his dignity by being clothed...with clothes.

We must also consider not only the effect of the image on the observer but also how the process of creating the image affects both the model and artist too. It is often stated that the etiquette of the studio, in which the model disrobes behind a screen and no one other than the studio master speaks to him or her when nude, protects the dignity of the model.

In fact, even if we accept that such etiquette does to some degree remove the general indignity of baring all in front of others and the erotic charge that might otherwise be present when the model is attractive,  then it does so by objectifying the person. That is, it creates a situation in which we no longer view the model as a person, but as shaped flesh. We need to be aware, therefore, that this approach might still be participating, albeit in a different way, in the problem of today's understanding of the human person that the Pope is trying to remedy. Perhaps in removing one difficulty, we are replacing it with another.

There are two other misconceptions that are often cited in favour of the nude. First that it is part of the Christian tradition of art. Well, as I found out, not really. Christianity reduced drastically the degree of nudity in art as compared with the pagan art that preceeded it. Only with the Renaissance did we start to see it appearing in art beyond certain very carefully designated situations (eg. Adam and Eve, and the Baptism in the Jordan).

Even then, as we have already mentioned, the style is important. Only those artistic styles developed to portray the person bathed in the uncreated light of God and him are appropriate for nudity, says John Paul II, for, 'If it is removed from this dimension, it becomes in some way an object which depreciates very easily, since only before the eyes of God can the human body remain naked and unclothed, and keep its splendor and its beauty intact.’

The second misconception is that it is necessary to study the nude in order to paint the human person well in naturalistic styles. While there are methods of study that do require the artist to understand anatomy, there are alternatives. I remembered my time studying at a studio in Florence where I learned the academic method - a way of painting that developed first during the High Renaissance. Although we did study the nude daily, were using a method called sight-size, in which we were taught to disregard our awareness of what we were looking at and consider only the shapes in abstract. In other words, we learnt to paint accurately what we saw, not what we knew to be there. We did not build up a figure by first sketching a skeleton, then putting on muscles, skin and finaly clothes. Some other schools do this, but it wasn't necessary. We were led to believe by our teacher that we were follwing the method of the school of Spanish baroque naturalism of the 17th century. The Church in Spain at that time, and in contrast with Italy, forbad nude models, and so artists such as Velazquez and Zurburan never studied the nude as part oftheir training. They seemed to do pretty well despite this handicap!

This is a very short summary of a much longer article (10,000 words) that appears in The Beauty of God's House: Essays in Honor of Stratford Caldecott published by Cascade Books. You can get the full essay for free by downloading a file, here.