Is a man's lust for a woman—whether she is unveiled, veiled, or speaks alluringly—considered adultery, and is the woman sinful for not guarding her chastity, or does the sin fall solely upon the man?

It is incumbent upon a man to lower his gaze, and it is incumbent upon a woman to observe hijab and conceal her allure from non-mahram men. Whoever fails to do so is sinful. He who strives to lead others astray and tempt them bears an additional sin, for Allah the Almighty says: "Indeed, those who like that immorality should be spread [or publicized] among those who have believed will have a painful punishment in this world and the Hereafter." (Quran 24:19). A man allowing his gaze to wander to what Allah has forbidden is the adultery of the eye, for the Prophet, peace and blessings be upon him, said: "The adultery of the eyes is looking." And a woman going out unveiled or perfumed to attract attention exposes herself to severe warning, for the Prophet, peace and blessings be upon him, said: "Any woman who perfumes herself and passes by a gathering of people so that they may smell her fragrance is an adulteress."