Jesus was arrested by the Jewish leaders who wanted him put to death. They did not have the authority since they were under Roman rule so they took him to Pontius Pilate. Pilate understood that Jesus was innocent and that he had been handed over out of envy. He was looking for a way to release him, even offering to release him as part of the Passover feast.
"While he was sitting on the judgment seat, his wife sent to him, saying, 'Have nothing to do with that just Man, for I have suffered many things today in a dream because of Him.'" (Matthew 27:19)
We do not know the details of the dream but we realize her suffering must have been severe in order for her to attempt to influence Pilate in governmental matters. Somehow from the dream she was given revelation the Jesus was a "just Man" and she didn't want her husband responsible for his death.
This was a warning dream but the warning was not heeded. Pilate succumbed to the will of the Jewish rulers rather than stand up for what he knew was right. This is another case where character was revealed.
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