The question: What must I do to be saved (or a slight variation) is asked three times in the book of Acts. It is found in: 2:37 (Jews on the day of Pentecost); 16:30 (the Philippian Jailor) and 22:10 (the apostle Paul). We will shortly look at these accounts in more detail; but it is important for us to remember, it is Jesus who saves us and not our works.
Matthew 1:21, "She (Mary) will bear a Son; and you shall call His name Jesus, for He shall save His people from their sins". In Ephesians 2:8-9, For by you have been saved through faith; and that not of yourselves, it is the gift of God; not as a result of works, so no one may boast".
When we do what is commanded in Acts 2, 16 and 22, we are placed in a position where Jesus can save us. In Acts 2, Peter has just accused the Jews of crucifying the Son of God. Three thousand were pierced to the heart and said, Brethren, what shall we do?" Peter tells them in verse 38, "Repent and each of you be baptized in the name of Jesus for the forgiveness of your sins, and you will receive the gift of the Holy Spirit". The first thing that should be noticed, is that Peter did not tell them to believe. It is self-evident that they believed, or they would not have said, "what shall we do". Peter tells them to do two things in order to have their sins forgiven: 1) Repent; 2) Be baptized. Failure to do either one, or both of these commands would result in the Jews remaining in their sins. If they follow Peter's commands two results will follow: 1) their sins would be forgiven, and 2) they would receive the Holy Spirit as a gift.
The second place the question is asked is in Acts 16:30. Paul tells the jailer to "believe in the Lord Jesus, and you will be saved, you and your household". Some people think that the jailer simply believed in Jesus and was saved. However, if we continue reading the Bible says that they spoke the word of the Lord to him and to all who were in his house. And he took them the same hour of the night and washed their wounds; and he was baptized at once, he and his family. Notice, he was not told to wait until they had their "baptismal service"; he was baptized at once. He was told to believe (verse 31). They spoke the word of the Lord to him and his household (verse32). He was baptized (verse 33). Why was he baptized when Paul had told him in verse 31 to believe? Apparently he also had to be baptized in order to be saved. Paul must have told him that when he spoke the word of the Lord to him in verse 32.
The third time the question is asked is in Acts 22. Paul has been arrested in Acts 21. He begins to make his defense for his preaching in Acts 22. He sees a vision of the risen Jesus. He asked Jesus, "What shall I do, Lord" (verse 10). Jesus tells him to go into Damascus and he would be told what to do. Paul goes into Damascus. According to Acts 9:9 three days later Ananias comes to Paul. He tells Paul to rise and be baptized and wash away your sins, calling on His name (the name of Jesus).
In Acts 2, the people, on the day of Pentecost, were told to repent and be baptized and their sins would be forgiven. In Acts 16 the jailer is told to believe and he was told to be baptized in order to be saved. In Acts 22 Paul is told to be baptized and wash away his sins. If we put these three instances together, we find that we need to believe, repent and be baptized in to receive the forgiveness of sins, to be saved and to have our sins washed away.
Some people have said that an angel appeared to them and told them what they had to do to be saved. Others have received special revelation from Jesus. Let us look again at Paul's conversion, and since some say that an angel gave them a "special revelation", we will also look at the conversion of the Ethiopian eunuch or treasurer in Acts 8.
In Paul's conversion, he asked the Lord what he needed to do. Instead of telling him, the Lord told him to go into Damascus and he would be told what to do. He was told what to do by Ananias.
In the case of the Ethiopian eunuch or treasurer an angel knew where the treasurer was. See Acts 8:26, "the angel of the Lord said to Philip, "Rise and go toward the south to the road from Jerusalem to Gaza." Notice, the angel knew where the treasurer was, but the angel did not tell the treasurer what to do to in order be saved. In verse 29 the Holy Spirit knew where the treasurer was, but the Spirit did not tell him what to do in order to be saved.
How did Paul learn what he needed to do in order to be saved? A man told him! How did the treasurer learn what he needed to do? A man told him! Jesus had the opportunity to tell Paul, but Ananias told him. An angel and the Holy Spirit had the opportunity to tell the treasurer, but Philip told him. There is no record given that indicates we will learn what to do to be saved from a special revelation. The only way that we will learn will be through the Bible, God's inspired word.