[1Co 15:3 KJV] For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures;
[1Co 15:4 KJV] And that he was buried, and that he rose again the third day according to the scriptures:
Which is no different than the gospel that was preached to the Jews at Pentecost, though the focus of the words might be different. Jesus' death is what gives us remission from sins, period. There is no other way to be saved
Did you even read Acts 2:38 and 1 Corinthians 15:1-4
Nowhere in Acts 2:38 Nowhere, is the death, burial and resurrection of Jesus Christ mentioned. The Gospel of Grace (1 Corinthians 15: 1-4 was was given to Paul and Paul alone.
If you believe you were saved through repentance and baptism you be wrong. We are saved only through Paul's Gospel!