Adam Clarke on Acts 26:10

Many of the saints - From what is said in this verse, it seems that Paul, before his conversion, was invested with much power: he imprisoned the Christians; punished many in various synagogues; compelled them to blaspheme - to renounce, and, perhaps, to execrate Christ, in order to save their lives; and gave his voice, exerted all his influence and authority, against them, in order that they might be put to death; and from this it would seem that there were other persons put to death besides St. Stephen, though their names are not mentioned.