In this passage, Hecate is saying that she will conjure a vision that makes Macbeth overconfident, and thus help push him toward his destruction. The quotation ends with Hecate's prediction that Macbeth will "bear his hopes above wisdom, grace, and fear," meaning that he will believe against all evidence that he will prevail over his enemies. This will make him pursue a self-destructive course of action. Her prediction comes true when Macbeth visits. He sees three visions, and from them gets the prediction that he can only be killed by a man "not of woman born," and then only when Birnam Wood (a forest) marches on the castle of Dunsinane. Her final observation that "security is mortals' greatest enemy" proves prophetic.