We need to notice that this phrase is introduced by the words, “what some call.” The phrase in question, then, was a slogan used by Jezebel and her children. By participating in the guild festivals (and so seeing the ceremonies that came with the sacrifices to the guild’s patron god), these Christians claimed they were better able to grasp Satan’s inner secrets. Alternatively, they felt they had mastered Satan’s deep things so that the dangers that came with the guild festivals were now no longer a threat to them.
24 But to the rest of you in Thyatira, who do not hold this teaching, who have not learned what some call the deep things of Satan, to you I say, I do not lay on you any other burden.