The core of the issue has already been mentioned. While many verses and arguments can be made, let us get to the crux of the matter.
"....whatsoever ye do, do all to the glory of God." 1 Cor. 10:31When our motive is simply this, to bring glory to God, modesty is never an issue. The problem is not "Old Testament Law," "long flowing robes," "or covering loins to thigh;" but the person dressing for their own glory and not God's. A person dressing for God's glory would not care to take a chance on wearing what God would be displeased with. A person dressing for God's glory would not desire to wear clothing that attracted sensually the glory to themselves.
Let's cover a few arguments:
Legalism: Legalism was an issue of the Pharisees in God's Word attempting to obtain salvation through the following of strict rules and guidelines. While I do know some who believe in a works salvation, most everyone of them are not "dressing for the occasion." When one accuses someone who believes in modesty of being a legalist, they are showing an ignorance in the term legalism and falsely accusing a brother. I repeat my first line, "No, it's not a matter of salvation."
Judging: The most quoted verse of the Bible as of 2010 is Matthew 7:1 "Judge not, that ye be not judged." How often do we here the immodest crying out that people need to quit "judging them?" First of all, please continue reading that passage in context (vs. 2) "For with what judgment ye judge, ye shall be judged:...(vs. 3) And why beholdest thou the mote that is in thy brother's eye, but considerst not the beam that is in thine own eye? (vs. 5) "Thou hypocrite, first cast out the beam out of thine own eye: an then shalt thou see clearly to cast out the mote out of thy brother's eye." So, the context of the passage is we need to make sure we are right before we help someone see how they are not right. It's not about one person better than another, but all about one person helping another. The reason this help would be rejected is because the person has a carnal mind.
It's Old Testament: Usually this is the argument used against a woman not wearing "that which pertaineth unto a man." (Deut. 22:5) The argument is that it is found in the Old Testament and not applicable to this age of grace. Or that this passage refers to the sin of cross dressing only. The New Testament simply says this in Romans 3:31 "Do we then make void the law through faith? God forbid: yea, we establish the law." Because we are saved by grace does not mean we make void the law (Old Testament), rather we establish it! Our life should be one that desires to be holy, to obey, to live a life that glorifies God.
You Can Be Immodest In a Skirt: True, you can, but that is why we have mothers who teach young ladies how to sit, how to walk, and how to stand. This "Excuse" is the worst to me. Young children also don't have a problem running around completely naked, but their comes a time when a parent teaches them they cannot do this anymore. Problem is mothers do not want to dress right, so they let their girls dress wrong and now ladies don't know how to sit, walk, and stand in even modest clothing because they are so used to sitting cross legged, legs spread, and bending over in front of the whole world. If one desires to dress to glorify God, they will easily be taught to stay modest in those clothes.
I'm the Same Person in Jeans as I am in a Skirt: No argument. You just as carnally minded in a skirt as you are in your jeans.
There are plenty of books and materials to study Scriptures on why to dress modestly. Everything changed when the mega churches started enjoying the money. The Fundamentalism influence ignored doctrine. Church members never matured. The "big churches" dropped their standards. The "little churches" followed the big church's example. I am sickened by the pastors who once taught, lived, and believed this, but have given in to their wife's carnal desires or their lusts and changed their stand.
In a room with other people, go to google images and search "modest clothes girls." It's happy, it's pure, its easy to look at with no fear of who is looking at you. Then let your wife search "girls in jeans" and ask if she would like her husband and sons to look at the screen?
I am an endorser of preaching and letting people have time to mature. But friends, there is a big difference between "I don't know" and "I won't, NO!" Clothes do not change the heart, but having a heart after God changes the clothes.
Revelation 4:11 reads, "Thou art worthy, O Lord, to receive glory and honor and power: for thou hast created ally hints, and for thy pleasure they are and were created."
Romans 9:23 reads, "And that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory."
We are to live for His pleasure and for His glory. Now, may we dress for the occasion!