AFFINITY, Affinitas, an Alliance, or Relation made between two Families, by Marriage. See ALLIANCE, and MARRIAGE. In this Sense, the Word stands contradistinguished to Consanguinity; which is a Relation by Blood. See CONSANGUINITY. In the Mosaical Law, there are several Degrees of Affinity, wherein Marriage is expressly prohibited; which yet seem not at all prohibited by the Law of Nature.—Thus, Levit. C. XVIII. ver. 16. a Man was forbid to marry his Brother’s Widow, unless he died without Issue; in which case, it became enjoined as a duty. So it was forbidden to marry his Wife’s Sister, while she was living, vv. 18, which was not forbidden before the Law, as appears from the instance of Jacob. The ancient Roman Law is silent on this Head; and Papinian is the first who mentions it; on occasion of the Marriage of Caracalla—The Lawyers who came after him, stretched the Bonds of Affinity so far, that they placed Adoption on the same Foot with Nature. See ADOPTION.



Affinity, according to the modern Canonists, renders Marriage unlawful to the fourth Generation, inclusive : But this is to be understood of direct Affinity; and not of that which is secondary, or collateral. Affinis mei affinis, non est affinis meus. See DEGREE, and COLLATERAL.

It is further to be observed, that this Impediment of Marriage, does not only follow an Affinity contracted by lawful Matrimony, but also that contracted by a criminal Commerce; with this difference, that this last does not extend beyond the second Generation; whereas the other, as has been observed, reaches to the fourth. See ADULTERY, CONCUBINE, FORNICATION, etc.

The Canonists distinguish three Species of Affinity—The first, that contracted between the Husband and the Relations by Blood of his Wife; and between the Wife, and the Relations by Blood of her Husband. The second, between the Husband, and those related to his Wife by Marriage; and the Wife, and those so related to her Husband.The third, between the Husband, and the Relations of his Wife’s Relations; and the Wife, and the Relations of her Husband’s Relations.—By the IVth Council of the Lateran, held in 1213, it was decreed, That none but the first Kind was any real Affinity; the rest being mere Refinements, which ought to be set aside. Tit. de Confung. & Affin.

The Degrees are reckoned after the same manner in Affinity, as in Consanguinity; and therefore differently in the Canon Law from what they are in the Civil Law. See DEGREE.

The Word is formed of the Latin Affinis, Neighbour;of ad, and finis, Boundary, Limit.

The Romanists talk of a spiritual Affinity, contracted by the Sacrament of Baptism and Confirmation. — In that Church, a Godfather may not contract Marriage with his Goddaughter, without a Dispensation. See GODFATHER, BAPTISM, etc.