Your opening comment went straight for Ephesians 2. You said,
Ephesians 2:8 Salvation is by grace through faith in Jesus and not by works, which would make water baptism a work towards repentance. John said I must decrease and Jesus increase. John's water baptism was only for repentance as being prepared for the coming of the Lord as the water represented the washing away of sin, or as John put it....
Instead of staying with the narrative in Acts 2, you ascribe baptism as a work and then assign it to Johns Baptism of repentance.
To be clear, you are correct to say Johns Baptism was for repentance. However, Peter clearly groups repentance with baptism FOR the forgiveness of Sins.
We know only God can forgive sins, so why do you think Peter says what he says? Again, Peter is grouping repentance with baptism for the forgiveness of sin. He later goes to say that they will receive the Holy Spirit as a result.
I guess the thing i want to separate is this. Johns Baptism is for repentance. The Baptism Peter is speaking about is not a stand alone command. It involves repentance.
If we want to pull Ephesians 2 into the equation, we know we are saved by Gods grace. But it takes faith to believe that, and obey Gods word. Those in Acts 2 put their faith in Peters words and we're baptized and 3,000 were added to the church that day. I have no doubt they believed they were saved.
The reason I gave that of Ephesians 2:8 is to show that salvation is not by being dunked in water, but by that of God's grace through faith in Jesus and not by works. Many are taught that you have to work for God's salvation by water baptism being part of those works we need to do in order for God's salvation.
In Acts 2:14-36 Peter was speaking to the crowd on the day of Pentecost telling them these men were not drunk, but explaining that of Joels prophecy being fulfilled in the pouring out of the Holy Spirit that indwelled all of them in the upper room that day. Peter continues preaching Christ to them in whom they did not know and had crucified Him.
All that Peter spoke pricked their hearts and they said unto Peter and the rest of the apostles what shall we do? Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.
In John's baptism it was not done in the name of Jesus Christ as He hadn't come yet, but done in preparation for the coming of Messiah to prepare you the way to come to Christ through repentance to receive Him as Lord and Savior. Now we read Peter saying to repent first and be baptized in the name of Jesus Christ and you will receive the gift of the Holy Spirit.
This is the same thing we read in Acts 10:44-48 that we should not forbid others to be baptized in water, but it is not for receiving the Holy Spirit or for repentance, but symbolic as being washed in the blood of Christ.
Are people adding the word water to Acts 2:38 by traditional teachings as the word water is not there or does it mean being baptized in the Holy Spirit after repenting first, accepting Jesus as Lord and Savior and then receiving the indwelling of the Holy Spirit.