God is so quiet

[Wyrd of Gawd]

I'm no expert, but I have read people claim that Paul was a somewhat drastic departure from the previous understanding of Christianity.

Paul and people around him invented Jesus à la L. Ron Hubbard. And why do I think that? Because Paul said it himself repeatedly. He constantly claimed that he has received his knowledge directly from Jesus. Meaning no apostles and no actual Jesus, no oral tradition, that it all came down from heaven direct to his ear, either via another vision of his Christ or the Lord God himself; like

Galatians 1:11-12   I want you to know, brothers and sisters, that the gospel I preached is not of human origin. I did not receive it from any man, nor was I taught it; rather, I received it by revelation from Jesus Christ.

Galatians 1:15-16  But when God, who set me apart from my mother’s womb and called me by his grace, was pleased to reveal his Son in me so that I might preach him among the Gentiles, my immediate response was not to consult any human being.

Or "1 Peter" (book that was not written by mythical Jesus Peter) where writer identifies himself as an "apostle" and not a "disciple" of Jesus Christ, meaning those who made careful search and inquiry into the Hebrew scriptures in order to get the answers from the "Spirit of Christ within them". So not witnesses or somebody who knew somebody who knew somebody who knew Jesus:

1 Peter, 1:10-12 Concerning this salvation, the prophets who prophesied of the grace that was to be yours made careful search and inquiry, inquiring about the person or time that the Spirit of Christ within them indicated, when it testified in advance to the sufferings destined for Christ and the subsequent glory. It was revealed to them that they were serving not themselves but you, in regard to the things that have now been announced to you through those who brought you good news by the Holy Spirit sent from heaven - things into which angels long to look!

Considering that Paul's writings date before the gospels, writer of Mark reverse-engineered a cosmic savior deity from Paul into a flesh-and-blood man on earth doing a sloppy job. Because he made numerous geographical mistakes among other mistakes of Roman law, Hebrew law etc.
Then the other writers of Gospels simply plagiarize Mark with some re-writes so that Mark's story becomes increasingly improved in Matthew and Luke; and by the time John's story is written, Jesus has become a cosmic deity from the very creation of the universe who strides around Judea fearlessly declaring to all that he is God almighty made flesh.

Paul also fought other religions or should I say "Christianities" because that term Christianity did not exist and it will not come in use until the 2nd century. Even Paul was said to be Nazorean.
One of his conflicts is with what he calls top three "pillars" of the Jerusalem church were named Cephas, James and John. Like Pontius Pilate or Caiaphas, these real people wind up as fictionalized characters in the Gospels, becoming Jesus' top three disciples: Peter, James and John. In fact, Paul only refers to a "Peter" once (Gal. 2:7-8), and it's still up for debate whether this is a scribal insertion, or if Paul meant Cephas, or a different person altogether.
Paul is quite paranoid about their group being "false believers," and brags he "did not submit to them even for a moment" (Gal. 2:4-5). Paul even accused "Peter" of being a hypocrite for not eating with uncircumcised Gentile Christians, which Mosaic law forbids and which is absurd because if Jesus existed then he would had settled these matters decades earlier. So Paul accepts them grudgingly as his own apostles and then Mark made them into Jesus'.
Also by Paul's time, communion rituals involving bread and a cup of wine or water had long been a staple feature of the pagan mystery faiths found throughout the Mediterranean world.
Paul was very aware of this, so what does he do? He simply calls other regions that do this "fakes" 1 Corinthians 10:21 "You cannot drink the cup of the Lord and the cup of demons too; you cannot have a part in both the Lord's table and the table of demons."
This is far from the only thing that Paul rips-off, because for starters the honorary title of the cult gods in the mysteries was Kyrios, "Lord" - the exact same word used in the NT for Jesus; Paul called himself the "father" of his converts, just as leaders of the Isis cult; his declaration of brotherhood is also present in the other Hellenistic mystery religions; in his letters his doctrines are called mysteries etc. and they are all proclaimed fakes and inventions of the devil, something that Christians today still hold to other religions and religions that brought Christianity.

Excellent comments.