17. Acts 2:38 was only for the Jews, because they killed their Messiah.
Consider the following verses:
Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: (Matthew 28:19)
And he said unto them, Go ye into all the world, and preach the gospel to every creature. (16) He that believeth and is baptized shall be saved; but he that believeth not shall be damned. (Mark 16:15 & 16)
And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem. (Luke 24:47)
Jesus told the apostles to go someplace and do something. He told them to take their message to every nation and to every individual. And…they were to begin at Jerusalem. What began in Acts 2:38 is for everyone.