"The next day, because he [Lysias] wanted to know for certain why he [Paul] was accused by the Jews, he released him from his bonds, and commanded the chief priests and all their council to appear, and brought Paul down and set him before them. Then Paul, looking earnestly at the council, said, 'Men and brethren, I have lived in all good conscience before God until this day.' And the high priest Ananias commanded those who stood by him to strike him on the mouth. Then Paul said to him, 'God will strike you, you whitewashed wall! For you sit to judge me according to the law, and do you command me to be struck contrary to the law?' And those who stood by said, 'Do you revile God's high priest?' Then Paul said, 'I did not know, brethren, that he was the high priest; for it is written, "You shall not speak evil of a ruler of your people"'" (Acts 22:30-23:5).
It appears that the soldiers did not interrogate Paul at all after they realize he was a Roman citizen whom they had unlawfully prepared to scourge. They leave Paul alone for the remainder of the day, but they must do something with him. Commander Lysias, still not knowing precisely what Paul was accused of by the Jews, decided to call the Jewish high council to order the next day (i.e., the Sanhedrin).
Paul looked intently at the council. Was he trying to see if any of his old cronies, from his former days as a persecutor, were present? Paul addressed the council by stating that he had lived in "good conscience before God until this day." His manner of life had been consistent with his level of knowledge, but this is not to say that he had lived perfectly (cf. I Tim. 1:15). This is a powerful statement when one considers Paul's life and activities both before and after his conversion. From our modern perspective, it teaches us that one can potentially do terrible things (like persecute Christians to death) and have an approving conscience all the while. The conscience is not an infallible guide. Proverbs 14:12 teaches - "There is a way that seems right to a man, but its end is the way of death." The conscience is only helpful to the extent that it has been properly trained. Prior to his conversion, Paul was misinformed about Christianity; it was not a false religion. But, since he sincerely believed that it was, his conscience did not trouble him (at least not at first; cf. 9:5) as he zealously labored to destroy the church. Today if one's conscience approves of his activities, it is no proof of their correctness. However, if one is troubled by his conscience it suggests he is considering or has already participated in something which he has doubts regarding the correctness of. In that case where one has doubts, abstaining from the action in question is the appropriate course (cf. Rom. 14:23).
After Paul affirmed that he continued to live in good conscience before God, the high priest ordered Paul to be struck on the mouth. What a rude interruption! He was offended by the implications of Paul's statement; namely, that one could turn his back on Judaism and do so with the blessing of a good conscience! After being struck, Paul retaliates verbally by calling the man a hypocrite. Paul knew they had no right under the Law of Moses to strike him (cf. Deut. 25:1,2), and yet they claim to be judges and upholders of the law! Paul is then informed that it was the high priest whom he was speaking against. A simple reading of the text seems to have Paul then apologizing for his harsh words, acknowledging the inappropriateness of speaking "evil of a ruler." It is quite possible Paul had no idea this man was the present high priest since the office changed rapidly in that era because of politics (28 different men were made high priests between the years of 37 to 70 AD). In his commentary on page 311, Wayne Jackson makes an interesting case, however, for the position that Paul was speaking by inspiration (cf. Matt. 10:17-20) and may have simply been saying that he did not recognize him as a high priest since he certainly didn't act like one!