Source: Birger A. Pearson, "Jewish Sources in Gnostic Literature," Jewish Writings of the Second Temple Period, ed. Michael E. Stone (Philadelphia: Fortress, 1984) 479.
"...the Gnostic pattern featuring the 'blasphemy' or 'vain claim' of the Demiurge--itself based upon Jewish texts and exegetical traditions--occurs in a number of extant Gnostic texts. Yet the differences among them in details seem to preclude the literary dependence of one text upon another. What is found here is a common tradition, subject to refinement in this or that Gnostic book."
I wonder what Jewish sources did with the "blasphemy" and "vain claim" of the Demiurge. Granted, one can interpret certain Jewish writings to claim that God has an intermediary. Wisdom of Solomon seems to present wisdom as a personified extension of God. Philo refers to a logos, which he called a "second God." Targumim present a memra speaking for God.
Do these ideas contradict Jewish monotheism? I'm not sure how Jews in those periods would have answered that. Maybe they thought the intermediary was like the Alan Rickman character in Dogma: a seraph who acts as the voice of God, since God's real voice is so powerful it would kill us. After all, the Bible often vacillates back and forth between an angel speaking and God speaking (e.g., Genesis 22; Exodus 3; etc.), so perhaps God had an angelic spokesperson early on in Jewish tradition. But, back to my original query, I don't think Jewish tradition ever saw this intermediary as evil, as Gnosticism does. So I wonder what Pearson has in mind when he says Jewish sources discussed the vanity and blasphemy of the Demiurge.
I also refer to this quote because it can help me in terms of my Fishbane paper. Michael Fishbane seeks to identify inner-biblical exegesis, in which one passage interprets, clarifies, and interacts with another passage. But is passage A necessarily interacting with passing B? Maybe it's referring to something in the general culture, rather than passage B per se. One way Pearson dismisses the "textual exegesis" possibility is by asking: are the two passages too different for one to have used another? If so, then we can't dogmatically claim that passage A interprets passage B. Unfortunately, as I've shown in past posts, Fishbane sometimes assumes that passage A interacts with passage B, when there are clear differences between the two.