When the three angels came to visit Avraham, they asked where Sarah was. They were told that she is in her tent.
The Keli Yakar explained that this was an indication of the wonderful trait of modesty, that Sarah possessed. It was in the merit of such modesty, that she was given a child at her advanced age.
There are numerous Mitzvot observed, when a woman has this trait of modesty. She fulfills the commandment to “Be holy.” She also fulfills her obligation to love and fear Hashem. She acts in a way that sanctifies the Name of G-d. She also fulfills not putting a stumbling block in front of a blind person, by avoiding dressing provocatively.
She walks in the way of G-d and she fulfills the commandment of cleaving to Him. She attains a certain nobility in the manner that she carries herself.
The Vilna Gaon added that the adornment of a woman, is her modesty. It is not only how she dresses, but it is also reflected in the way she carries herself. Women demonstrated this nobility, in that they did not participate in the sin of the spies. And the daughters of Tzlofchad demonstrated their wisdom and love for the land, in the request made to Moshe Rabbeinu for an inheritance.
These beautiful traits of modesty began with our Mother Sara, and is fulfilled by all of the modest women of today.