Ayoub al-Sakhtiyani أيوب السختياني · The Book of Marriage

"What becomes unlawful (for marriage) through breast-feeding is that which becomes unlawful through lineage."

"I said: 'O Messenger of Allah, why do you choose wives from among Quraish and not from among us?' He said: 'Do you have anyone in mind?' I said: 'Yes, the daughter of Hamzah.' The Messenger of Allah said: 'She is not permissible for me (to marry); she is the daughter of my brother through breast-feeding.'"

"Suckling once or twice does not make (marriage) prohibited."

"My paternal uncle Aflah asked permission to enter upon me after the (Verse of) Hijab had been revealed, but I did not let him in. The Prophet came to me and I asked him (about that) and he said: 'Let him in, for he is your paternal uncle.' I said: 'O Messenger of Allah, the woman breast-fed me, not the man.' He said: 'Let him in, may your hands be rubbed with dust, for he is your uncle.'"

"The rest of the wives of the Prophet refused for anyone to enter upon them on the basis of that type of breast-feeding, meaning breast-feeding of an adult. They said to 'Aishah: 'By Allah, we think that what the Messenger of Allah told Sahlah bint Suhail to do was a concession which was granted by the Messenger of Allah only with regard to breast-feeding Salim. By Allah, no one will enter upon us, nor see us on the basis of…

It was narrated from Anas that the Messenger of Allah manumitted Safiyyah and made her freedom her dowry.

"The Messenger of Allah said: 'What differentiates between the lawful and the unlawful is the Duff, and the voice (singing) for the wedding.'"

"I heard Muhammad bin Hatib say: 'What differentiates between the lawful and the unlawful is the voice (singing).'"