The Melodious Voice of a Woman is 'Awrah

“It is better she learn from a woman because the melodious voice (naghmah) of a woman is ‘awrah. The proof for that is what is reported from the Messenger of Allāh (peace and blessings of Allāh be upon him) that he said: ‘Tasbīḥ is for men and clapping for women [when alerting the imām in ṣalāh to an error].’” (al-Nawāzil, SOAS PhD Thesis, p. 184)

“His, Exalted is He, saying: ‘Do not soften the speech lest someone with sickness in his heart becomes desirous.’ It has been stated about this that she is not to soften the voice to men in a manner necessitating suspect people desiring her. There is proof in this that this rule is for all women, on it being prohibited for them to soften the voice to men in a manner necessitating desiring them and from which it can be inferred [the women] desire [the men]; and [there is] proof that it is best for a woman not to raise her voice where men will hear it. There is evidence in this that a woman is forbidden from Adhān, and thus have our imāms opined. Allāh, Exalted is He, said in another verse: ‘They must not stamp their feet so that their hidden ornaments are known.’ Since she is forbidden from causing her anklets being heard, her speech – when she is non-elderly and temptation is [thus] feared from her – is more worthy of being forbidden.” (Aḥkām al-Qur’ān, 5:229)

“In al-Wāqi‘āt, transmitting from al-Nawāzil, it states: For a woman to learn Qur'ān from a woman is better than she learn from a blind man because her melodious voice is ‘awrah. Thus, [the Prophet] (peace and blessings of Allāh be upon him) said: ‘Tasbīḥ is for men and clapping for women [when alerting the imām in ṣalāh to an error].’ Thus, it is not permissible for a man to hear it.” (Ḥalbat al-Mujallī, 1:599)