Albert Barnes Commentary Matthew 20:3

"And he went out about the third hour, and saw others standing in the marketplace idle;" — Matthew 20:3 (ASV)

About the third hour. The Jews divided their days into twelve equal parts, or hours, beginning at sunrise, and ending at sunset. This was, therefore, about nine o'clock in the morning.

Standing idle in the marketplace. A place where provisions are sold in towns. Of course many frequent such places; and it would be the easiest place to meet people, and find employers. They were not, therefore, disposed to be idle, but were waiting in the proper place to find employers.