You know, I am not sure about what the pp meant with that quote, but I still think the advice of dressing modestly is good regardless. In your case, a pair of comfortable modest jeans and a modest shirt that does not have hanging bits (and a good pair of sneakers like you said

) would be both modest and safer for you than other modest but not practical options.
You know, I think the OP on this thread was correct in her definition of modesty (probably not from this thread, but from one of the similar ones) as being akin to “not bragging, etc.”
If modesty “means refusing to unveil what should remain hidden” (
CCC 2521) it follows that modesty in clothing would entail not
needlessly flaunting one’s body.
I don’t think this means not flaunting by just not showing skin (take, for example, “Madonna’s” costumes in 80s (?) - underwear on top of clothes isn’t modest, either.) And as everyone on this thread knows, clothes which are unecessarily tight can also be immodest.
Not flaunting is partly determined culture (
CCC 2524) and more finely determined by what activities a person is engaged in. To go around showing more skin/shape than is acceptable in a culture without good reason would be flaunting one’s body.
If a person living in a culture where the customary clothing was just a grass skirt were to start going around without the grass skirt for no good reason, the person would be immodest within his/her own culture. Wearing a swimming suit to do clerical work would be flaunting one’s body as there’s no practical reason to be that scantily clothed while filing.
Because much of what makes clothing modest or immodest is circumstantial (dependent on the culture & era and what activities one is engaged in) to try and define modesty according to specific articles of clothing is not a valuable exercise.
Modesty is an expression of intention, as well, as has already been discussed. Obviously, if you’re intending to attract sexual attention or lead others into sin you’re not being modest.
But, I think if you choose clothing that is practical for the tasks one is undertaking and does not show any more of the body than is acceptable in the culture and necessary for the task, then you’re doing fine. (Hence the absurdity of the “no-pants-for-women” arguments.) Clothes are just clothes; not that important in the grand scheme of things, and I must admit I can’t justify giving them much more thought than the preceding couple of sentences.
@chevalier et. al. The above is why I think spaghetti straps aren’t considered acceptable for Mass; the only reasons for wearing them are either a) to keep cool or b) to show off one’s beauty as a part of a formal celebration.
As to a) most churches are climate-controlled as to b) while we ought to dress for Mass in a way that acknowledges how important the occasion is, glamorous clothes are out of place because we aren’t there to celebrate our own beauty (I think this is also why the tux for men idea in another thread doesn’t fit.)
I don’t like spaghetti straps because of the bra-strap showing issue; underwear should never be visible, IMO.