You guys are miles beyond me in this theological stuff so I have to stick with what I read in the scriptures...
As I see it, there was no redemption taught in Acts 2...There was remission of sins, not redemption...There is water baptism required for the gift of the Holy Spirit...
This does not appear to be the same gospel of grace taught by Paul, as I see it...
It isn’t.
"And [pray] for me, that I may open my mouth boldly, to make known THE MYSTERY OF THE GOSPEL, For which I am an ambassador in bonds: that therein I may speak boldly, as I ought to speak" (Eph. 6:19,20). There is a MYSTERY of the gospel. Something that was SECRET until revealed to the Apostle Paul. Meaning something that was NOT known before Paul. The mystery is a truth which was INTENTIONALLY KEPT HIDDEN until revealed to and through the APostle Paul: He says it was "kept secret SINCE the world began (Rom 16:25),..."in other ages..NOT made known,"From the BEGINNING of the world..HID IN GOD (Eph. 3:5,9), "hid from ages and from generations" (Col. 1:26).
Now you tell me, if it was HID IN GOD until REVEALED to Paul,how could it be the same as Peter and the 11 had? Great, simple common sense says it could NOT be the same.
Again, I would say Peter is giving a sermon and not writing a theological document. By Peter going into detail about the resurrection after speaking of the Christ crucified, that is redemption.
As for receiving the Holy Spirit AFTER baptism we do know there were 120 receiving the Holy Spirit before Peter's sermon. That is why we must look at all of the scriptural evidence. When we go to Acts 10 we see Cornelius and his household hear the Gospel, believe, receive the Holy Spirit and then water baptized. When we go to Acts 15 we see Peter say the following:
6 Now the apostles and elders came together to consider this matter. 7 And when there had been much dispute, Peter rose up and said to them: “Men and brethren, you know that a good while ago God chose among us, that by my mouth the Gentiles should hear the word of the gospel and believe. 8 So God, who knows the heart, acknowledged them by giving them the Holy Spirit, just as He did to us, 9 and made no distinction between us and them, purifying their hearts by faith.
Peter tells all assembled he delivered the same gospel he received and preached it to the Gentiles (Cornelius et. al.) If we look at the sermon given by Peter in Acts 2 and compare it with the sermon in Acts 10, we see little difference. We see the same results.
Any other endeavor to say sometime in Acts Paul instructed Peter on the gospel to preach to Cornelius is just not there. Paul is giving a missionary report in Acts 15 before the Jerusalem council not revealing a new gospel.