And these are the generations of Esau, the father of the Edomites . Though Esau had two names, yet in this place the second name refers to his posterity, who are called Idumeans. For, to make it appear what God had bestowed upon him for the sake of his father Isaac, Moses expressly calls him the father of a celebrated and famous people. And certainly, it served this purpose not a little, to trace the effect and fulfillment of the prophecy in the progeny of Esau. This was that Anah that found the mules .
Mules are the adulterous offspring of the horse and the ass.
Moses says that Anal was the author of this connection. Moreover, we learn hence, that there is more moderation among brute animals in following the law of nature, than in men, who invent vicious admixtures. These are the kings that reigned, etc . We must keep in memory what we have said a little before, that reprobates are suddenly exalted, that they may immediately fall, like the herb upon the roofs, which is destitute of root, and has a hasty growth, but withers the more quickly. To the two sons of Isaac had been promised the honor that kings should spring from them.