The third hour. It seems that at this time the Jews divided the day, reckoned between sunrise and sunset, into twelve equal parts, the length of these divisions varying according to the season. The day in Palestine at longest consisted of fourteen European hours twelve minutes, and at shortest of nine hours forty-eight minutes, so that the difference between the longest and shortest division of the so called Jewish "hour" was twenty-two minutes.
It is usual to consider the Hebrew day as lasting from 6 a.m. to 6 p.m., the sixth hour corresponding to our noon, the first hour being 7 o'clock and the third 9 a.m. This estimate, though not absolutely correct, is near enough to the fact to serve all expository purposes.
The four periods mentioned in the parable are quarters of the working day, in which a proportional part of the day's wages might be earned. Standing idle in the marketplace. The Greek agora, the Roman forum, and the Eastern marketplace, was the usual place where idlers and expectant labourers gathered together.
Such a scene may often nowadays be witnessed in Oriental cities, and indeed at our own docks, and in many of our small country towns. It must be supposed that the labourers now hired either were not present when the householder first went forth, or that they had then rejected his offer, but now thought better of it.
And so, in the case of the others later on.