when we first meet macbeth he says"so foul and fair a day i have not seen"(1-3line40).who made this comment first in the play?why do you think shakespeare has the line repeated?

The witches use this same line in the first scene of the play. I believe the line is repearted to illustrate the duplicity of the characters involved. At this point, we see Macbeth, fresh from battle..... a proud and loyal man who love his country above all else. The witches' intentions are never in question, as they set out from the start to deceive...... as for Macbeth. He goes onto deceive himself.