Of course, but who are we trying to impress with our outer appearance by "dressing up"? I agree it is appropriate to dress in clean, conservitive clothing so a not to offend those around us but "dressing up" does not impress God and if we are scandelized by jeans or pants on women in church then it would seem to me a matter of the heart of the worshiper.
In Sunday school a few months ago we were dicussing pet peeves and were directed to approach someone we did not know and share a personal peeve with them. An older women came up to me, she was dressed to "the nines" and said in a very snotty tone that her pet peeve was people wearing flipflops to church. Oh my! Give me a break!
By dressing up, we aren't trying to impress anyone. We do it to honor our King. It is part of worship and homage, just like we try to have beautiful music, church buildings, live rather than plastic flowers, vestments, kneel for communion, etc. -- a matter of respect. This all used to go without saying.
I agree 100% that it is a matter of the heart of the worshipper. It is not a matter of being scandalized; nor am I trying to legalistically prescribe what should be worn, but it seems to me that we (the church in general, and particularly in the United States) are misusing the fact that we should not exclude someone based on what they wear to worship to make a different and false argument that our dress for worship irrelevant, so long as it does not offend. Such a rule, of course, begs the question of what's offensive, but beyond that, misses the point of what worship is.
Naturally God is most concerned that we appear with a broken and contrite heart. But if there's any point to church architecture, fine music, bells, vestments, and to name biblical examples: palm waving, anointing with fine oil and perfume, bowing, kneeling, etc., then for anyone who thinks about, it would seem to that flip flops should be out. The whole point of the worship exercise is to show the sacred nature of what is occurring: the Word of God is being preached and the sacraments administered. These are extraordinary gifts, so the response should be worshipfully extraordinary: special building, special vestments, special music, and yes, special dress.
I realize that those appearing in jeans and flip flops mean no harm and that there are those out to impress by dressing-up, but it's a bit shallow to think that's the reason our predecessors in the faith wore their Sunday best for Sunday worship up until the 1960's. It doesn't impress God, but, He accepts it as His due.