Adam Clarke on Matthew 26:15

Thirty pieces of silver - Τριακοντα αργυρια, thirty silverlings; but στατηρας, staters, is the reading of the Codex Bezae, three copies of the Itala, Eusebius, and Origen sometimes; and στατηρας αργυριου, silver staters, is the reading of the famous Basil MS. No. 1, in Griesbach, and one copy of the Itala.

A stater was the same as the shekel, and worth about 3s. English money, according to Dean Prideaux: a goodly price for the Savior of the world! Thirty staters, about 4l. 10s. the common price for the meanest slave! See Exo 21:32. The rabbins say, thirty סלעין selain of pure silver was the standard price for a slave, whether good or bad, male or female. See tract Erachin, fol. 14, and Shekalim, cap. 1. Each selaa weighed 384 barley-corns; the same number was contained in a shekel; and therefore the shekel and the selaa were the same. See the notes on Gen 20:16, and Exo 38:24.