Is covering a girl's face an obligation (fard), and is she sinful if she does not cover it?

We have previously affirmed the obligation for a mature woman to cover her face. Adhering to the niqab is a widespread virtue, and holding fast to it when people turn away from it is a revival of the Sunnah, for which the reward is great. Therefore, be keen on it and endure hardship for its sake. However, if unbearable harm results from it, especially from someone in authority, then there is no sin in uncovering the face due to necessity, and you return to the original ruling once the necessity ceases. At that time, do not go out except for an urgent need.