Matthew Poole and continuators on Leviticus 18:12

12 Thou shalt not uncover the nakedness of thy fathers sister : she is thy fathers near kinswoman .

Thy Aunt by the fathers side, as the next verse speaks of the Aunt by the mothers side. If Amrams example be alledged to the contrary, see on Exod. 6. 20.

Heb. thy fathers flesh, a member and product of the same flesh from which thy father came. z (i. e.) of his wife, as the next words explain it. And as a man may not marry his aunt, so neither may a woman marry her Uncle, there being altogether the same distance in kindred, and the self-same reason of the law. And for the examples of Abraham, Amram, Othoniel, &c. to the contrary, they were before the publication of this law, by which it pleased God to restrain the liberty allowed formerly when the holy seed was in a narrower compass, and fewer persons, which altered the case. For in that regard there was a time when God allowed brethren and sisters to marry, to wit, when there were no other in the World, which was the case of Adams immediate children. We learn from hence, that the same degrees are forbidden in consanguinity or kindred by blood, and in affinity or kindred by marriage.

Marginal references: chap. 20. 19.; Heb. flesh. Gen. 37. 27.