{4} Then said Paul, I wist not, brethren, that he was the high priest: for it is written, Thou shalt not speak evil of the ruler of thy people.

(4) We must willingly and from the heart give honour to magistrates, although they are tyrants.

People's New Testament

23:5 I wist not, brethren, that he was the high priest. It was contrary to the law of Moses to revile one in high authority (Ex 22:28). Paul's reply to the charge that he had violated the law has been variously explained. Howson gives what appears to me the most probable view:

I did not take thought, at the moment, in my indignation over the command to smite a defenseless prisoner on trial, that he was the high priest. I am well aware that it is said, Thou shalt not speak evil of the ruler of thy people.''

His words were an apology for his hasty speech. I wist not is used in the sense of I did not bear in mind.

Wesley's Notes

23:5 I was not aware, brethren, that it was the high priest - He seems to mean, I did not advert to it, in the prophetic transport of my mind: but he does not add, that his not adverting to it proceeded from the power of the Spirit coming upon him; as knowing they were not able to bear it. This answer admirably shows the situation of mind he was then in, partly with regard to the bystanders, whom he thus softens, adding also the title of brethren, and justifying their reproof by the prohibition of Moses; partly with regard to himself, who, after that singular transport subsided, was again under the direction of the general command. Exod 22:28.

Jamieson-Fausset-Brown Bible Commentary

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].

Matthew Henry's Concise Commentary

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.