Ghayrah is a spiritual barrier that protects Hijab and averts Tabarruj (exposure of beauty), Sufoor (exposure of the face) and free mixing. Such jealousy is the spiritual force placed by Allah The Almighty within the slave in order to protect His sanctities, his own honor, and chastity from every criminal and treacherous person. This type of Ghayrah is a praiseworthy characteristic in Islam and is a permissible form of Jihaad as confirmed by the Messenger of Allah, : “Indeed, Allah has Ghayrah, and the faithful believer has Ghayrah, and the Ghayrah which Allah has is provoked when a believer commits that which Allah has forbidden.” [Al-Bukhari and Muslim]
The Prophet, , also said: “Whoever is killed in defense of his family [or his honor] is a martyr.”[At-Tirmithi]
Hijab is a great sanctity that develops Ghayrah which is provoked because of the violation of such sanctities and causes high moral characteristics to be inherited by children from their parents, that is, the woman's jealousy for her honor, her guardians' jealousy for her, the believers' jealousy for the Mahrams (non marriageable people) of the believers to be violated or injured in such a way as to wound the woman's dignity, chastity, and purity, even if with an unlawful look from a non-Mahram man.
Hence, such jealousy is the opposite of being a Dayyooth (a man who approves of indecency committed by his womenfolk), and the jealous man in this regard is the opposite of the Dayyooth who approves of the violations committed by the females under his guardianship with no sense of jealousy for them.
This is why the purified Sharee‘ah has removed all means that lead to the violation of Hijab and weakness of character. Below is the valuable statement of Shaykh Ahmad Shaakir in his comment on the Marfoo‘ Hadeeth (i.e., a statement of a Companion that is attributed to the Prophet, , on the authority of Abu Hurayrah, may Allah be pleased with him, “No woman applies perfume as she is going to the Masjid except that Allah would never accept prayer from her - until she takes a bath to cleanse herself from it as she takes a bath to cleanse herself from Janaabah [ceremonial impurity].” [Ahmad]
Ahmad Shaakir said,
Consider, O Muslim man, and consider, O Muslim woman, this severe threat given by the Messenger of Allah to the woman who comes out perfumed with the intention to go to the Masjid to worship her Lord - that no prayer would be accepted from her until she takes a bath to cleanse herself from it in the same way that she takes a bath to cleanse herself from Janaabah, in order for the traces of perfume to vanish entirely.
Consider that in comparison to what is done by the immoral, impious and dissolute women of our time, who falsely claim to belong to Islam, and how they are helped by impious men who dare to oppose Allah The Almighty, His Messenger and the axioms of Islam, pretending that there is no harm if the woman exposes her face, and comes unveiled, and mixes with men in markets and places of entertainment and impiety. They dare to claim that Islam has not forbidden her to travel alone on what they call a knowledge mission. They also make it permissible for her to assume political positions. Nay! Consider these women in the markets who expose their private areas which Allah The Almighty and His Messenger ordered to be screened: you see the woman having uncovered her head and adorning herself, exposing her breasts, chest, back, arms and armpits, and wearing clothes that almost cover nothing at all, but rather reveal the parts of her body beneath the clothing, and display them in the most provocative of ways. Moreover, those evildoings are even seen during the day in Ramadan, and neither they, nor those men, or rather those Dayyooth, whom Allah has made their guardians, feel ashamed. You may then wonder, are they really Muslim men and women?
Let me say that if you like to know the superiority of Hijab and women covering their faces from non-Mahram men, consider the status of the veiled women and how they are surrounded by modesty, and how they keep themselves far from crowding with men in the markets, and maintain themselves from falling into vice or being vulnerable to the unlawful looks of the impious. Consider also the status of their guardians, and the extent of self-respect they have, and how they guard that virtue in their Mahrams. Then, compare that with the status of the woman who displays her beauty, who exposes her face and looks at the faces of men, whereas virtues have fallen from her in proportion to the extent that she exposes her face and proves herself to be immoral. You may see an impious woman who exposes her face, talk with an impious man, and think, due to the state in which they are, that they are spouses with a marriage contract to which Abu Hurayrah, may Allah be pleased with him, was made witness; and even if her Dayyooth husband sees her in such a state, he would not do anything, and we seek refuge with Allah The Almighty from the death of jealousy and an evil return.
Where is this type of husband in comparison to the Bedouin who divorced his wife when he saw a non-Mahram man looking at her? When he was rebuked for that he composed a famous poem explaining that he was going to refrain from that which he desired due to the number of those who desired share it with him, and that if flies fell on his food, he would lift his hand from it while still desiring it and that lions avoid drinking from a source of water if they see dogs drinking from it. Where are these exposed women in comparison to the noble Arab woman whose headcover once fell from her face, and thereupon she picked it up with one hand and covered her face with the other - and a line of poetry was composed about what she did? Higher and more glorious is the story of the two daughters of Madyan's old man, as told by Allah The Almighty (what means): {Then one of the two women came to him walking with shyness.} [Quran 28:25] It is narrated on the authority of ‘Umar, may Allah be pleased with him, through an authentic chain of transmission, that he said commenting on this verse, “She came walking with shyness, covering her face with her garment, and she was neither a brash acid-tongued woman, nor was she in the habit of coming out of the house and going here and there.”
This noble verse also implies graciousness, chastity and modesty that made the old man's daughter attain such an amazing degree of self-preservation and caution, as shown from her saying to him: {"Indeed, my father invites you that he may reward you for having given water to for us."} [Quran 28:25] Thus, she attributed the invitation to its source – that of the tongue of her father, in order to be far from suspicion.