Is covering the face and hands obligatory in the hijab, is she who does not do so considered (unveiled/improperly covered), and is there a clear text from the Qur’an or Sunnah that obliges their covering and prohibits their uncovering?

Scholars have differed on the obligation of a woman covering her face and hands in front of non-mahram men. The madhhab of Imam Ahmad and the soundest opinion within the Shafi'i madhhab hold it to be obligatory, while Abu Hanifa and Malik view it as not obligatory but rather recommended. Nevertheless, the jurists of the four madhhabs agree on the obligation of covering when there is a fear of fitna (temptation/strife) and the corruption of the times. Among the evidences for its obligation are: Allah's saying, "that they should draw their outer garments (jalabib) over their persons" (Quran 33:59), and "And when you ask them (his wives) for anything, ask them from behind a screen (hijab)" (Quran 33:53), and "and to draw their veils (khumur) over their bosoms (juyubihinna)" (Quran 24:31). Similarly, the permission for elderly women (Al-Qawa'id min An-Nisa') to lay aside their outer garments indicates the obligation of hijab for younger women, as well as the noble hadith, "The woman is awrah (a private part/nakedness); if she goes out, Satan lures her," and the prohibition for a woman in ihram from wearing the niqab and gloves.