Matthew 20:2 - Coke's Commentary on the Holy Bible

For a penny a-day— A denarius, or Roman penny, in value about seven-pence halfpenny of our money,—which hence it seems was the usual price of a day's service among the Jews, as Tacitus tells us it was among the Romans, Annal. Matthew 1:17. It is therefore justly mentioned, Revelation 6:6 as a proof of the great scarcity of provisions, when a measure, or choenix of wheat, which was the usual allowance to one man for a day, and was about an English quart, was sold at that price. See Doddridge.