Medieval Church law at the time forbade marriage within seven degrees.

It is unclear, however, whether members were forbidden marriage or liaisons with women outside the walls.

They were unable to marry because the law forbade marriage between blacks and whites.

However, as part of its population control measures, the Chinese government later forbade polygamous marriage altogether under family law.

The law forbids marriage between an uncle and niece, even those who are only half-related.

Listen, not every state forbids marriage between the races, and the rest have to respect it once it's happened where it's allowed.

The heart rises at it; God forbids such marriages; you dishonour your white hair.

The Shakers never forbade marriage for such individuals, but considered it less perfect than the celibate state.