you are correct that God does not contradict Himself and all Scripture is true and must be able to be harmonized. we also must realize that the Church received both an oral Sacred Tradition from the Apostles in addition to the written Scriptures.
given that, we know we are saved by grace and grace is a gift from God Himself. grace can not be earned nor is it deserved, we are all sinners and under the penalty of sin. when Christ died for our sins on the cross and then rose from the dead, before He ascended to heaven He gave the Apostles authority to go into all the world, make disciples of all nations by baptizing them and teaching them. He also told them He would send another comforter, which we know was the Holy Spirit on Pentecost.
the Holy Spirit only works within the Body of Christ, the Church. the Church is the instrument the Holy Spirit uses to baptize believers. the Church, possessing the keys to the kingdom, has no authority at all except that given to it from Jesus, thru the Apostles, to their successors down to today.
so we see Peter preaching in Acts 2:38 and clearly stating baptism is for the remission of sins and receiving the Holy Spirit. Paul makes there clear there is only one baptism, no where in the Bible does anyone speak of “water baptism” and “spirit baptism” Baptism is the Sacrament whereby the Holy Spirit thru the Church washes away the sins of the recipient, the Holy Spirit takes residence in the soul, and the baptized become “in Christ” and part of the Body of Christ, outside of which there is no salvation.
the Catholic position is the only one where all the Scriptures come together and make sense. the Baptist must say there are two baptisms and then explain what “water baptism” is for.
the big confirmation of the Catholic position is the Church itself. one only read the Church Fathers to see they all believed in baptismal regeneration, the Baptist position doesn’t appear until the 16th century.
finally, when the bishops at Nicea said “ we acknowledge one baptism for the forgiveness of sins”, where were the “true” Christians to oppose them with the “two baptism” theory? where were they? 1,300 years away is the answer.
“we also must realize that the Church received both an oral Sacred Tradition from the Apostles in addition to the written Scriptures.”
Really? Where is it? Was it whispered from Pope to Pope?
No.
What is called sacred tradition is the accumulated beliefs of Roman Catholics for the last 1500 years. It picks and chooses which of the ‘Church Fathers’ to follow. And it was NOT handed down from Pope to Pope since Peter was in Rome. Even the Roman Catholic church doesn’t teach that.
Purgatory was not taught in secret to one Pope after the other until someone let it slip.
It was invented hundreds of years later.
Yet the Apostles taught it all. Openly.
“You yourselves know how I lived among you the whole time from the first day that I set foot in Asia, 19 serving the Lord with all humility and with tears and with trials that happened to me through the plots of the Jews; 20how I did not shrink from declaring to you anything that was profitable, and teaching you in public and from house to house, 21 testifying both to Jews and to Greeks of repentance toward God and of faith in our Lord Jesus Christ. 22And now, behold, I am going to Jerusalem, constrained by the Spirit, not knowing what will happen to me there, 23except that the Holy Spirit testifies to me in every city that imprisonment and afflictions await me. 24But I do not account my life of any value nor as precious to myself, if only I may finish my course and the ministry that I received from the Lord Jesus, to testify to the gospel of the grace of God. 25And now, behold, I know that none of you among whom I have gone about proclaiming the kingdom will see my face again. 26Therefore I testify to you this day that I am innocent of the blood of all of you, 27for I did not shrink from declaring to you the whole counsel of God. 28 Pay careful attention to yourselves and to all the flock, in which the Holy Spirit has made you overseers, to care for the church of God, which he obtained with his own blood. 29I know that after my departure fierce wolves will come in among you, not sparing the flock; 30and from among your own selves will arise men speaking twisted things, to draw away the disciples after them. - Acts 20
“I did not shrink from declaring to you the whole counsel of God.”
Not most of it, or the parts I thought you should know, but “I did not shrink from declaring to you the whole counsel of God.”
But also notice the prophesy of Paul:
“I know that after my departure fierce wolves will come in among you, not sparing the flock; 30and from among your own selves will arise men speaking twisted things, to draw away the disciples after them.”