In the narrative of the Acts of the Apostles, Paul was called to appear before the Jewish Sanhedrin on the instructions of the commander of the Roman garrison in Jerusalem.
Ananias heard Paul's opening defense and commanded those who stood by him "to strike him on the mouth".
Paul describes him as a "whitewashed wall" (Greek: τοιχε κεκονιαμενε) and testifies that God would strike Ananias for this unlawful command.
[1] Theologian John Gill identifies Joshua ben Gamla as the high priest during the trial, for one possible explanation of Paul's remark.
[2] Quadratus, governor of Syria, accused Ananias of being responsible for acts of violence.