• Paternal and maternal aunts are likewise forbidden—that is, every sister of any of your fathers, however far up the line, and every sister of any of your mothers, however far up.
Whatever relatives remain beyond these are lawful, such as the daughters of your paternal uncles, the daughters of your paternal aunts, the daughters of your maternal uncles, and the daughters of your maternal aunts.
For this reason Allah has set out this crucial distinction between what is lawful and what is forbidden in two places:
– In the present passage He explicitly names the seven prohibited categories and then states, “All others beyond these are lawful for you” (Qur’an 4:24).
– In Sūrah al-Ahzāb He expresses the same ruling in a different style: “And the daughters of your paternal uncles, the daughters of your paternal aunts, the daughters of your maternal uncles, and the daughters of your maternal aunts who emigrated with you” (33:50)—meaning that they are lawful, whereas any other blood-relatives are forbidden.

• As for those rendered forbidden through nursing (radāʿ), they mirror the categories forbidden by lineage on the side of the nursing woman and the owner of the milk:
  • The wet-nurse becomes the child’s mother; her mothers are his grandmothers; her brothers and sisters are his maternal uncles and aunts; her own children are his brothers and sisters, while he in turn is an uncle to their children. The same applies to the man to whom the milk is attributed.
  • With respect to the child himself, the prohibition does not spread to any of his relatives except to his own descendants.
• The phrase in the verse concerning step-daughters—“who are in your care from the women you have married” (Qur’an 4:23)—describes what is most common and highlights the supreme wisdom behind the ruling: when the girl is being raised in your household as though she were your own daughter, it is only fitting that she be among your unmarriageable kin.