Bat Melachim - A Princess
Bat Yisrael - Daughter of Yisrael
"The full glory of a king's daughter is within; her raiment is inwrought with gold" Tehillim 45:14
Casual or improper dress exhibits a lack of self-esteem and self-respect, while tzniut (modesty) entails being aware of the importance of the Bat Yisrael (Daughter of Israel) and ensuring that she is properly protected.
In reference to modesty the Jewish woman is called a Bat Melachim. This indicates that modesty is born out of a realization of the Jewish woman's royal status. Knowing she is a Bat Melachim guarantees that she dresses appropriately. Moreover, casual dress projects an undisciplined, wayward attitude to life, while modesty entails a style of life in which one is careful to fulfill halacha (Jewish law) and avoid all forms of intermingling.
When a woman is particular about modesty, and ensures that her dress is appropriate for a mother or future mother in Klal Yisrael (the Jewish People), her clothes generate splendor and prestige. Her aristocratic manner of dress bears witness to the fact that she has consecrated her life to the service of her Creator. Rather than make worldly desires the essence of her life, she uses the means given to her in a proficient and praiseworthy manner for the furtherance of her true role - to set up a home from which Torah and Yirat Hashem (Fear of G-d) shall shine forth.
Just as the priestly garments of the Kohen (Priest) are described by the Torah as magnificent (Shemot/Ex. 28:2), for they demonstrate that the Kohen is engaged in a holy and distinguished service, so too, the garments of the true Bat Yisrael demonstrate that her days are filled with true values. Hence, the strength displayed by the effort she has made to find such refined clothes reveals her inner royalty and splendor.