Paul is using irony and a rhetorical question to say that the Galatians are acting as though someone has put a spell on them. He does not really believe that someone has put a spell on them. Alternate translation: "You behave as if someone has put a spell on you!" (See: [[rc://en/ta/man/translate/figs-irony]] and [[rc://en/ta/man/translate/figs-rquestion]])
Paul speaks of his clear teaching of Jesus being crucified as if he had put on public display a picture of Jesus being crucified. And he speaks of the Galatians having heard his teaching as if they had seen the picture. Alternate translation: "You yourselves heard the clear teaching about Jesus being crucified" (See: [[rc://en/ta/man/translate/figs-metaphor]])