Two women shall be grinding at ( ἐν) the mill. In the absence of mills turned by wind or water, which were of much later invention, every household had its own little handmill, worked by women of the family or by slaves (Exodus 11:5; 16:21; Isaiah 47:2).
"Two stones, about eighteen inches or two feet across, rest one on the other, the under one slightly higher towards the centre, and the upper one hollowed out to fit this convexity; a hole through it, in the middle, receiving the grain.
Sometimes the under stone is bedded m cement, raised into a border round it, to catch and retain the flour, or meal, as it falls. A stick fastened into the upper one served as a handle. Occasionally two women sit at the same pair of stones, to lighten the task, one hand only being needed where two work together, whereas a single person has to use both hands".
"Two women were busy in a cottage at the household mill, which attracted me by its sound To grind is very exhausting work, so that, where possible, one woman sits opposite the other, to divide the strain, though in a poor man's house the wife has to do this drudgery unaided".
St. Luke (Luke 17:34) adds a third situation to the cases mentioned by our Lord, viz. "two men in one bed," or on one dining couch.