God gave Peter the keys.
Peter used them for the very first time to open the kingdom of God to sinners at Acts 2:38.
This audience was sinners.
We are to duplicate this command to sinners, not contradict it.
This command to sinners included repent and be baptized in the name of Jesus Christ for the remission of sins....
That would be news to Paul, who had to chastise Peter later for his dissimulation in the body of Christ.
I am become a fool in glorying; ye have compelled me: for I ought to have been commended of you: for in nothing am I behind the very chiefest apostles, though I be nothing.
God gives all His ministers the keys to the kingdom, which He still holds in His hands (Rev 1:18). He doesn't turn doctrine-making over to them. The apostles spoke as the prophets, what God gave them to speak and write in Scripture.
The keys are to unlock the mystery of God in the church by ministry, of the Scriptures, not to become a lawgiver, judging our brethren by our own rule.
Peter is not the Rock of the church, and right after he was given the keys, he tried to use them to rebuke Jesus, and the Lord turned round and rebuked him as Satan's minister. So much for those keys in his hands.
I am not a Roman Catholic.
This audience was sinners.
Every audience is sinners, until they repent and believe the gospel.
Once they repent and believe, no more sinners, but saints.
God does His work of salvation in a moment so soon as He sees the faith of His Son born in the heart, so soon as He sees the blood of the Lamb of God upon the doorposts of their souls.
No 'sinners prayer' nor water baptism needed. Only confession of Jesus from the heart.
Being saved by water baptism is a carnal minded work to boast of.
God doesn't cover His believers, that He has saved by hearing of faith, with a cloud overhead and a pillar of fire before and behind, until they get to the nearest water, lest they die in their sins before they can accomplish 'Acts 2:38'.
We are to duplicate this command to sinners, not contradict it.
No one does. If someone wants to say the very words God gave in that Scripture, then do so with a blessing.
Preaching that one verse for doctrine by which to judge other confessing believers as unsaved is false accusation of the brethren by false doctrine of Scripture.
You people are like the JWs. So soon as you meet someone confessing Jesus as Lord, you lurk and lie in wait for the opportunity to spring your special little doctrine on them. They want to insert Jehovah, and you want to insert Acts 2:38.
I was in a similar separatist group that wanted to insert 'holiness living' according to our standards.
It's all the same spirit of proselytization to draw away disciples after ourselves from the one body of Christ.
I've been there as a leading minister and done that, and now I am free of it, and count it all as but dung, that I may win Christ, and count myself as victorious for 'winning' another one to our group.
I now can freely enjoy good fellowship with all they confess Jesus as Lord.