Acts 16:24 - Coke's Commentary on the Holy Bible

Made their feet fast in the stocks,— It is generally supposed that these were the cippi, or large pieces of wood used among the Romans, which not only loaded the legs of prisoner's, but sometimes distended them in a very painful manner. So that the situation of Paul and Silas must have been very affecting, especially if they lay with their bare backs, so lately scourged, on the ground, as it is very probable they did. This circumstance renders their songs of praise the more remarkable. Beza explains the original word of the numellae, or pieces of wood containing five holes, in which the neck, hands, and feet were confined in the most uneasy posture that can well be imagined.