Nasai

Hazrat Hamzah radi Allahu anhu’s daughter was, in terms of lineage, the paternal cousin of the Messenger of Allah sallallahu alayhi wa sallam, and thus marriage with her was permissible for him. For this reason, Hazrat Ali radi Allahu anhu proposed marriage to her. However, she was also his foster niece, because both the Messenger of Allah sallallahu alayhi wa sallam and Hazrat Hamzah radi Allahu anhu had been breastfed by Thuwaibah. In this respect, they were foster brothers. Therefore, marriage to his (foster) brother’s daughter was not permissible, because a foster niece is like a biological niece.

Hadith Commentary:
Vocabulary of the Hadith:
TANAWWAQ:
Originally "tatanaawwaqu," which is derived from "neeqah."
It refers to something superior and excellent; here, it means to select or to prefer.

Benefits and Issues:
Hamzah radi Allahu anhu was the uncle of the Messenger of Allah sallallahu alayhi wa sallam, and he was two or four years older than him.
He was nursed by Abu Lahab’s slave woman, and this slave woman, named Thuwaibah, also nursed the Prophet sallallahu alayhi wa sallam. Abu Lahab freed Thuwaibah at the time when the Prophet sallallahu alayhi wa sallam had already migrated to Madinah.
(Tabaqat Ibn Sa’d, vol. 1, p. 108)
There is much disagreement regarding the name of this daughter of Hamzah radi Allahu anhu.
The well-known name is ‘Amaarah, who was with her mother in Makkah, and after the return from ‘Umrat al-Qada, she came to Madinah with the Prophet sallallahu alayhi wa sallam, and he sallallahu alayhi wa sallam entrusted her guardianship to Ja’far radi Allahu anhu.
And from this hadith it is understood that
it is permissible to offer a girl from one’s family or tribe in marriage to a person of knowledge and virtue, and in this regard, in light of another narration, her beauty and attractiveness may also be mentioned,
because beauty and attractiveness are also a source of attraction.

Explanation:

➊:
These are the seven relationships: (1) mothers, (2) daughters, (3) sisters, (4) paternal aunts (phuphi), (5) maternal aunts (khala), (6) nieces (brother’s daughters), (7) nieces (sister’s daughters).

Grandmothers (both paternal and maternal) are included under “mothers,” and granddaughters (both son’s and daughter’s daughters) are included under “daughters.”

There are three types of sisters: full sisters (from both parents), half-sisters (from the father’s side), and half-sisters (from the mother’s side).

Similarly, nieces (brother’s and sister’s daughters) are included even if they are from a lower degree, and paternal aunts (phuphi) are included whether they are full, half (from the father’s side), or half (from the mother’s side).

Likewise, the paternal aunts of the father, grandfather, mother, and grandmother are all prohibited (for marriage), and the same applies to maternal aunts (khala) accordingly.