The medieval period is sometimes stereotyped as having an unhealthy fear of witchcraft — a phobia which would carry over into the New World and the famous Salem witch trials.  Chapter 9 of Heiko Oberman’s Masters of the Reformation outlines some of the late medieval discussions about witchcraft and one of the saner voices.  Oberman focusses on Martin Plantsch (died 1533), the preacher of the Tübingen Collegiate Church.  Plantsch was apparently regarded as the best preacher of his time.  He was that rare blend of clergy who combine in abundant measures superb preaching, theological scholarship, and effective personal pastoring.  One of Plantsch’s scholarly interests happened to be witchcraft.  In fact, in 1507, he published a treatise on the subject, developed out of a series of sermons.

According to Oberman, Plantsch’s main goal was “to shatter scientifically the spell of witchcraft” (163).  His method involved uniting “the contributions of theology and the natural sciences,” as well as appealing to “church, Scripture, and the fathers” (165).

What I find most interesting about Plantsch’s work (as described by Oberman) is his discussion of whether witches and demons could engage in sexual relations and produce offspring.  Popular opinion held that they could.  In fact, the children of witches were usually suspected (if not condemned) by the very fact that they were the children of witches.  Oberman begins his chapter with the story of Anna Spülerin of Ringingen.  She had been suspected of being a witch because her mother was suspected of being a witch.  She went through horrible suffering, but lived to tell the tale.

Now here is the paragraph where Oberman lays out Plantsch’s argument against demons being able to procreate with humans:

Plantsch’s goal of rational enlightenment became even more conspicuous where he denied that offspring could issue from a supposed sexual union between a woman and the devil.  He insisted that witchcraft could not be inherited to the sense in which inheritance is normally understood.  For a witch could not really have sexual intercourse with a demon or with the devil himself since neither spirit has a body capable of producing sperm.  No, the ‘best’ the devil could do would be malevolently collect and preserve semen from a man and artificially inseminate a ‘witch.’  But the offspring of this ‘union’ would still be a completely human child like every other baby.  (171-172)

Seems to make sense.  It also seems to make sense, then, to apply the same reasoning to that thorny passage of Genesis 6:1-4, where the “sons of God” get married to “the daughters of man.”  If demons can’t impregnate humans, and if demons are of exact like-nature with angels (apart from being fallen), then no angels can impregnate humans.  “Sons of God” must mean something different in that passage.  I’ve worked that out in my sermon on that passage.  Plantsch’s view was not widely accepted and I wonder if that had anything to do with Genesis 6.  Hmm….