In the past, the Church has spoken pretty clearly on modesty. Pope Benedict the XV said, in 1921 (though it sounds as if our current Pope Benedict could be speaking of today!):
One can not sufficiently deplore the blindness of so many women of every age and station. Made foolish by a desire to please, they do not see to what degree the indecency of their clothing shocks every honest man and offends God. Most of them would formerly have blushed for such apparel as for a grave fault against Christian modesty. Now it does not suffice to exhibit themselves on public thoroughfares; they do not fear to cross the threshold of churches, to assist at the Holy Sacrifice of the Mass, and even to bear the seducing food of shameful passions to the Eucharistic Table, where one receives the Heavenly Author of Purity.
St. Padre Pio insisted on modesty, going so far as to turn women away from confession if they were immodestly dressed. His brothers eventually posted on a sign informing women that they must enter the confessional wearing a skirt at least 8 inches below the knee. This would certainly be quite shocking if it were to happen today. But St. Padre Pio didn't refuse immodestly dressed women to confession because he was cold-hearted or self-righteous. When probed, he replied, "Don't you know what pain it costs me to shut the door on anyone? The Lord has forced me to do so. I do not call anyone, nor do I refuse anyone either. There is someone else who calls and refuses them. I am His useless tool."
Which is really the point of the whole issue. Modesty is pleasing to God because it respects and honors our bodies and souls as His creations. It's pretty simple at the heart of it. Of course there's a lot of deep theology regarding the very real differences between men and women and how those differences perfectly complement each other and reflect the perfect nature of God that I'm glossing over, but well, I'm not a theologian. So I'll leave the trickier stuff to the experts for now and point everyone towards Pope John Paul II's Theology of the Body and the myriad compendiums and summaries that have been published on it to help us lay folk understand the message.
Now, what constitutes modesty in the modern world? That gets tricky, and add up how many Catholic women there are in the world and that's how many different answers you'll get if you ask. In discussing modesty with other Catholic women, I've come up with a basic outline that most seem to agree with, keeping in mind that this refers to daily dress, and not to say, mountain biking or exercising.
- No tank tops
- Nothing that shows cleavage
- Skirts at or below the knee
- No "stripper shoes"
Beyond that, it's harder to pin down. Full-time skirt wearing in particular seems difficult to commit to. I mean, besides evangelical fundies, who wears long skirts every day, anyway? Won't people think you're weird? Won't people think you're just being self-righteous and over-zealous (especially if you're a convert)? I know these are the concerns I have as I'm currently discerning full-time skirt wearing. But if we arrive at our decision slowly as we pray, asking the Spirit for guidance, considering Scripture and Tradition and desiring to please our Lord (and let's not forget to look to Our Lady as our model of femininity and modesty), then the answer is probably easy, though the practice might be difficult. As with all things, when we seek with a sincere and humble heart, we can trust the Spirit to guide us. Modesty is something we do to please the Lord, not a contest over who's sleeves and skirts are longest.
All things consider, modesty is one of many facets of my conversion, and something that I'm still in the process of discerning (have you noticed I like that word? Discerning. It sounds so proper and dignified, much nicer than "thinkin' about"). I try to keep my husband's desire to see me attractively dressed in mind, and to remember that modest and frumpy are not the same thing. I don't wear anything I wouldn't wear to Mass. I haven't worn pants (outside of my garden and the gym) in awhile. I don't wear tank tops, though I do wear short sleeves, and I try not to wear anything that comes lower than a couple inches below my collarbone. Mostly I continue to look to Our Lady as my model of modesty and keep my heart open to the guidance of the spirit.