THE GOSPEL ACCORDING TO MATTHEW - Chapter 20 - Verse 2

Verse 2. A penny a day. The coin here referred to was a Roman coin, equal in value to about 14 cents, [about 7d.] The original denotes the Roman denarius, dhnariou a silver coin, which was originally equivalent to ten asses, (a brass Roman coin,) whence its name The consular denarius bore on one side a head of Rome, and an X or a star to denote the value in asses, and a chariot with either two or four horses. At a later period the casts of different deities were on the obverse; and these were finally superseded by the heads of the Caesars. Many specimens of this coin have been preserved. The preceding cuts will show the usual appearance of the coins.

It was probably at that time the price of a day's labour. See Tobit v. 14. This was the common wages of a Roman soldier. In England, before the discovery of the mines of gold and silver of South America, and consequently before money was plenty, the price of labour was about in proportion. In 1351, the price of labour was regulated by law, and was a penny a day. But provisions were of course proportionally cheap; and the avails of a man's labour in articles of food were nearly as much as they are now.

{x} "penny" Mt 18:28