David Guzik comments at enduringword.com:
God will strike you, you whitewashed wall! How did Paul say these words in Acts 23:3? It would have helped to hear Paul’s tone of voice as he rebuked the high priest; was it an outburst of anger, or was it a calm, collected rebuke with that much more weight to it?
Whatever the tone, the rebuke was entirely accurate and justified.
The high priest indeed was a whitewashed wall; a white veneer of purity covering over obvious corruption.
The high priest was also not only to be the administrator of the law, but the example of it. His command to have Paul struck was in fact contrary to both the spirit and the letter of the law. Deuteronomy 25:1-2 says only a man found guilty can be beaten, and Paul had been found guilty of nothing.
The Ananias who was high priest at this time was a man who did no honor to the office. He was well known for his greed; the ancient Jewish historian Josephus tells of how Ananias stole for himself the tithes that belonged to the common priests.
“He did not scruple to use violence and assassination to further his interests.” (Bruce) Because of his pro-Roman politics, he was, however, brutally killed by Jewish nationalists.
God will strike you: “Paul’s words, however, were more prophetic than he realized. Ananias’ final days – despite all his scheming and bribes – were lived as a hunted animal and ended at the hands of his own people.” (Longenecker)
However, Paul agreed that it was wrong to speak evil of the ruler of your people (Exodus 22:28), considering the office more than the man; but claims he did not know that Ananias was the high priest. Some think he did not know because Paul’s eyesight was bad. This is an inference from Galatians 4:14-15 and 6:11, as well as from early written church traditions. Others think that Paul is being sarcastic here, with the idea “I didn’t think that anyone who acted in such a manner could be the high priest!”
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