Note 5 at Acts 9:5: Saul knew who he had been persecuting and he no doubt had a very good idea who this was who was talking to him, but as verse 6 says, he was astonished and apparently found it hard to believe that he had been so wrong. However, in the awesome presence of God, he had the good sense to recogniz that whoever this was, was Lord.

Note 6 at Acts 9:5: The word used for pricks is the Greek word "kentron" meaning "to goad." It is the same word that is used in Acts 2:37 to describe the conviction of the Holy Ghost on the people who listened to Peter's sermon on the day of Pentecost.

A goad was an iron instrument for urging on oxen, horses, and other beasts of burden. For Saul to kick against the pricks meant that Saul was fighting against the reproof and conviction that the Lord had been giving him. This leaves no doubt that Saul had been under conviction for some time, possibly since the stoning of Stephen.

As mentioned in note 6 at Acts 5:28, page 598, sometimes those who protest the loudest are the ones who are the most convicted. Saul's severe persecution against the Christians was just a manifestation of the conflict that was going on inside him. He had been trained to adhere to the law in the strictest sense but there was a growing revelation inside him that Jesus had fulfilled the law.