Secondly

(it should not be an adornment in and of itself).

Allaah says (interpretation of the meaning):

“… and not to show off their adornment…” [al-Noor 24:31]. The general meaning of this phrase includes the outer garment, because if it is decorated it will attract men’s attention to her. This is supported by the aayah in Soorat al-Ahzaab (interpretation of the meaning):

“And stay in your houses, and do not display yourselves like that of the times of ignorance” [al-Ahzaab 33:33]. It is also supported by the hadeeth in which the Prophet (peace and blessings of Allaah be upon him) said: “There are three, do not ask me about them: a man who leaves the jamaa’ah, disobeys his leader and dies disobedient; a female or male slave who runs away then dies; and a woman whose husband is absent and left her with everything she needs, and after he left she made a wanton display of herself. Do not ask about them.”

(Narrated by al-Haakim, 1/119; Ahmad, 6/19; from the hadeeth of Faddaalah bint ‘Ubayd. Its isnaad is saheeh and it is in al-Adab al-Mufrad).

Thirdly:

(It should be thick and not transparent or “see-thru”)

- because it cannot cover properly otherwise. Transparent or see-thru clothing makes a woman more tempting and beautiful. Concerning this the Prophet (peace and blessings of Allaah be upon him) said: “During the last days of my ummah there will be women who are clothed but naked, with something on their heads like the humps of camels. Curse them, for they are cursed.” Another hadeeth adds: “They will not enter Paradise or even smell its fragrance, although its fragrance can be detected from such and such a distance.”

(Narrated by Muslim from the report of Abu Hurayrah).

Ibn ‘Abd al-Barr said: what the Prophet (peace and blessings of Allaah be upon him) meant was women who wear clothes made of light fabric which describes and does not cover. They are clothed in name but naked in reality.

Transmitted by al-Suyooti in Tanweer al-Hawaalik, 3/103.