What does it mean that Paul received authority from the chief priests in Acts 26:10?
Paul had been granted official delegated authority by the chief priests, placing him in a position to act against believers. In his pre-salvation persecution, he used that authorization to shut up many saints in prison in Jerusalem, believing he ought to oppose the name of Jesus of Nazareth.
Les explains that the same Greek word for power or authority appears here as in Ephesians, where principalities and powers have authority. In Acts 26:9-10, Paul describes his pre-salvation experience when he thought he ought to do many things contrary to the name of Jesus of Nazareth. He says he did this in Jerusalem and shut up many saints in prison, having received authority from the chief priests. Les emphasizes that this means Paul was put in a position where he could do what he was doing; it was delegated authority that enabled his persecution of believers.
Which thing I also did in Jerusalem: and many of the saints did I shut up in prison, having received authority from the chief priests; and when they were put to death, I gave my voice against them.