Rashi on Deuteronomy 24:6/רש"י על דברים כ״ד:ו׳

1לא יחבל NO MAN SHALL TAKE [THE LOWER OR THE UPPER MILLSTONE] AS PLEDGE — i.e. if one comes to demand a pledge through the court for his debt he should not take as a pledge anything by which food is prepared (Bava Metzia 113b, 115a).

2רחים is the lower,

3ורכב is the upper millstone.