Luke 23:9

‘And he questioned him in many words, but he answered him nothing.'

But all his attempts to make Jesus respond, and they were apparently considerable, failed. As a sheep that before His shearers is dumb, so He opened not His mouth (Isaiah 53:7, compare Acts 8:32). He had stated His case to Pilate, and had convinced him of His innocence. It was clear to Him what Herod's view of the situation was and He saw no point in responding to attempts to bully or cajole Him into putting on a show. So He maintained a dignified silence. He was now resigned to the fact that justice was not available to Him whatever He did. He had them all summed up in His own mind, and knew them exactly for what they were.