“There will be two women grinding together, the one will be taken, and the other will be left.”
The same picture is now applied to women grinding in the mill together, the one turning the stone, the other pouring in the grain. Very often this would be mother and daughter, or two sisters. But the one will be taken and the other left. No more vivid picture could be given of the ‘invisibility' of the Kingly Rule of God, for no one, apart from the individuals, and they might be wrong, could be sure who was under the Kingly Rule of God and who was not (compare Luke 17:21).