What is the legal consequence regarding affinity arising from lawful intercourse (watu' mubah)?
Chapter on What is Prohibited to Marry and Combining Between Them and Other Matters
Al-Mughni
Book of Marriage
Primary text
Lawful intercourse, occurring within a valid marriage or legal ownership, establishes the prohibition of affinity (tahrim al-musaharah) by consensus. It also renders the woman forbidden to the man's relatives (mahramiyyah) because the prohibition is permanent, established through a lawful act, which is analogous to kinship (nasab).