"What are the Qur'anic verses that address the ruling on a woman covering her face, and is it obligatory or recommended?"

The seclusion of women and the covering of their faces is an obligation supported by evidence from the Holy Qur'an, the Sunnah of the Prophet, and sound reasoning.

From the evidence in the Qur'an: 1. The Almighty's saying: "And let them draw their headcovers over their bosoms," which indicates the obligation to cover the face because it is a place of beauty and temptation, and prohibits displaying adornment except to those who are explicitly exempted. 2. The Almighty's saying: "And as for the elderly women who do not expect marriage, there is no blame upon them if they put aside their outer garments without displaying their adornment. But to modest themselves is better for them," which specifies the ruling for elderly women and indicates the obligation of hijab for young women. 3. The Almighty's saying: "O Prophet, tell your wives and your daughters and the women of the believers to bring down over themselves [part] of their outer garments," which Ibn Abbas interpreted as covering the face. 4. The Almighty's saying: "There is no blame upon them concerning their fathers or their sons," which shows the exemption of mahrams (unmarriageable kin) from the obligation of seclusion.

From the evidence in the Sunnah: 1. The Hadith: "If one of you proposes to a woman, there is no blame upon him if he looks at her, if he only looks at her for the purpose of proposing," which indicates that anyone other than the suitor is sinful for looking at a non-mahram woman. 2. The Prophet's (peace be upon him) command to a woman who did not possess a jilbab (outer garment) to borrow one from her sister to go out to the Eid prayer area, which indicates the necessity of the jilbab. 3. Aisha's Hadith about the women who were wrapped in their mantles during Fajr prayer, and that if the Messenger had seen what they saw, he would have prevented them from attending the mosques. 4. Umm Salamah's question about women's train, which indicates the obligation to cover the feet, and feet are less tempting than the face and hands. 5. The action of the female Companions covering their faces with their jilbabs when riders passed by them while they were in a state of ihram, despite the prescribed practice in ihram being the uncovering of the face.

In addition to this, uncovering the face leads to harms such as temptation, the loss of modesty, the seduction of men, and leads to the mixing of women with men.