Commentaries
23:1-5 See here the character of an honest man. He sets God before him, and lives as in his sight. He makes conscience of what he says and does, and, according to the best of his knowledge, he keeps from whatever is evil, and cleaves to what is good. He is conscientious in all his words and conduct. Those who thus live before God, may, like Paul, have confidence both toward God and man. Though the answer of Paul contained a just rebuke and prediction, he seems to have been too angry at the treatment he received in uttering them. Great men may be told of their faults, and public complaints may be made in a proper manner; but the law of God requires respect for those in authority.
5. I wist not … that he was the high priest—All sorts of explanations of this have been given. The high priesthood was in a state of great confusion and constant change at this time (as appears from Josephus), and the apostle's long absence from Jerusalem, and perhaps the manner in which he was habited or the seat he occupied, with other circumstances to us unknown, may account for such a speech. But if he was thrown off his guard by an insult which touched him to the quick, "what can surpass the grace with which he recovered his self-possession, and the frankness with which he acknowledged his error? If his conduct in yielding to the momentary impulse was not that of Christ Himself under a similar provocation (Joh 18:22, 23), certainly the manner in which he atoned for his fault was Christ-like" [Hacket].