Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates that al-Bara' bin Malik had a beautiful voice. On one of the journeys of the Messenger of Allah (peace and blessings be upon him) he was chanting rajaz (verses) for him (peace and blessings be upon him). Meanwhile, when he came near the women (and their mounts), the Messenger of Allah (peace and blessings be upon him) said to him: "Be careful regarding the women (that is, take care of these beings as delicate as glass vessels)." So he fell silent. Muhammad bin Ishaq said: The Messenger of Allah (peace and blessings be upon him) disliked this because the women would hear his voice. This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.