Act 1
1. "Fair is foul, and foul is fair," is stated in line 10 by the witches in the opening of the play. The significance of this paradox is that it sets us up for the doubleness of the play. It means what is fair to the witches is foul to man.
2. "Though his bark cannot be lost, / Yet it shall be tempest-tossed," is stated in lines 24 and 25 by the first witch while she and the other witches are discussing a recent experience of hers with a sailor. The significance is that it gives us insight on the capabilities of the witches. It means the first witch can't destroy the sailor's boat, but she can make him miserable with a storm, meaning witches can only play with man, not destroy him.
3. "So foul and fair a day I have not seen," is stated in line 38 by Macbeth while him and Banquo discuss his defeat. The siginificance is Macbeth paraphrasing what the witches said. It means the day is fair because he won the battle, but foul because he's exhausted and is bleeding.
…