AFFINITY. There were several degrees See Lev. xviii. 7. & seq.of Affinity among the Hebrews, which were obstructions to Matrimony. For example, 1. The Son could not marry his Mother, nor his Father’s second Wife; 2. The Brother could not marry his Sister, whether she were so by the Father only, or by the Mother only, much less if she were thus related to him on both sides; 3. The Grandfather could not marry his Grandaughter, either by his Son or Daughter; 4. No one could marry the Daughter of his Father’s Wife; 5. Nor the Sister of his Father or Mother; 6. Nor the Uncle his Niece, nor the Aunt her Nephew; 7. Nor the Nephew the Wife of his Uncle by the Father’s side; 8. The Father-in-law could not marry his Daughter-in-law; 9. Nor the Brother the Wife of his Brother, while living, nor even after the death of his Brother, if he left Children. If he left no Children, the surviving Brother was to raise up Children to his deceased Brother, by marrying his Widow. 10. It was forbidden to marry the Mother and the Daughter at one time, or the Daughter of the Mother’s Son, or the Daughter of her Daughter, or two Sisters together.
It is true, the Patriarchs before the Law sometimes married their Sisters, as Abraham married Sarah, who was his Father’s Daughter by another Mother; and two Sisters together, as Jacob married Rachel and Leah; and their own Sisters by both Father and Mother, as Abel and Cain: But these Cases are not to be proposed as Examples, because in some they were authorized by necessity, in others by custom; and the Law as yet was not in being. If some other examples may be found, either before or since the Law, the Scripture expressly disapproves of them; as Reuben’s Incest with Balah his Father’s Concubine, and the Action of Ammon with his Sister Tamar, and that of Herod Antipas, who married Herodias his Sister-in-law, his Brother Philip’s Wife, while her Husband was yet living.