The following points can be made from a reading of Luke’s narrative of Paul’s conversion (Acts 9) and of his own recounting of it (Acts 22,26). (We will refer to the Apostle, even in his pre-conversion state, as Paul rather than Saul for sake of simplicity.) (This is also the subject matter of FAQ 34.)
1/ Paul was confronted directly and personally by Jesus Christ and heard Him speak audibly.
2/ Christ revealed Himself to Paul.
3/ Paul came to have faith in Christ. He addressed Him as Lord and surrendered his life to Him (Acts 9:6).
4/ Paul received a charge to preach (Acts 26:16-18).
5/ Strangely, it must seem to some, Christ commanded Paul to go into the city and await a messenger who would tell him something that was necessary for him to do. And it would seem it was a matter of faith to warrant such strong language. Jesus said it was something he must do (Acts 9:6).
(It was not information regarding his future ministry. Christ had already told him that, as noted in point 4, and Ananias added nothing to it.).
A person gets the sense from the narrative that all is not complete regarding Paul’s salvation experience. Christ did not pronounce him saved and Paul did not go on his way rejoicing, as the eunuch did in Acts 8 (v.39). He was left blind so as to force him to meet with the person that will be sent to him. It’s as though the newly-believing Paul needed an incentive to follow through on Christ’s directive.
The person that was sent to Paul was a man named, Ananias. His message to Paul was indeed a matter of faith. It regarded remission of sins and receiving the Holy Ghost (Acts 9:17-18; 22:16). This comports with Christ’s Own Great Commission to His ministers which involved remission of sins, to which is coupled the gift of the Holy Ghost. (See Jesus’ Great Commission throughout the Gospels and its fulfillment in Acts 2:38-39.) That leads us to the next point.
6/ During his encounter with Christ on the Damascus Road, Paul did not receive remission of sins. That occurred three days later when he was baptized (Acts 22:16).
7/ During his encounter with Christ, Paul did not receive the Holy Ghost (Acts 9:17). That, likewise, occurred three days later.
Jesus sent Paul away without remitting his sins or filling Him with the Holy Ghost. He brought conviction on Paul, as He alone can do (John 6:44), and prompted him to go to a commissioned man.
Implications
1/ There is no such thing as justification by faith alone. There is justification by faith, which is how the biblical expression is phrased. Justification, indeed, is based on faith in Christ, which leads a person to obey the required tenets of salvation, as Paul did. Justification involves remission of sins. And that occurs through water baptism in Jesus’ name. It was that way for Paul. And, it is so for everyone else. That was Peter’s declaration on the Day of Pentecost (Acts 2:38-39).
2/ Christ does not automatically remit our sins when we come to faith in Him. Paul’s example of conversion makes this fact clear. As per Jesus’ commission, ministers administer baptism in Jesus’ name, which plunges them into a mystical burial with Christ (Romans 6:3-5) and washes away their sins (Acts 22:16). Once the blood of Christ is applied through baptism, and the convert is into Christ (Romans 6:3), then future sins become covered as the person walks with Christ in the light (1John 1:7-9).
3/ A person who comes to believe in Jesus is not immediately filled with the Spirit at the initial moment of faith. This fact is proven by Paul’s own conversion experience and is corroborated by many other examples in Acts. (See Acts 8:14-17; 19:1-6.)
4/ Some people think that Paul taught in his epistles that salvation is merely by faith. But that was not his own experience. Therefore, it could not have been his teaching. (It was also not his ministry practice, as in the above reference of Acts 19:1-6.)
5/ Faith in Christ means believing and obeying what He prescribed for Christian salvation in the Great Commission.