Protestants are people who protested against the Catholic Church. But specifically they are people who used to be Catholic, who then became not quite as much Catholic.
There were other churches around during the height of Catholicism. Baptists have been around forever and various other churches were around as well. Catholics get the most publicity; many think the entire church was Catholic at one point.
That’s mostly because Catholics have always been expert at getting people’s money and also killing opponents and destroying their work. When you have the power and money, you dominate the narrative.
Luther was Catholic and wanted to stay in the Catholic Church, and he would have if they hadn’t booted him. Calvin copied Augustine on 90% of doctrine and Augustine is considered the Father of Catholicism.
Most of the doctrinal differences between denominations today is how much not-Catholic they are. Most denominations and churches will tell you that their sole authority is the Bible, but reading the doctrinal statements of all these churches lets you know someone aint giving authority to the Bible.
If all churches who said the Scripture was their authority actually had Scripture as their authority, there would be lots more unity. There isn’t. Why not? Because a lot of doctrine is formed not on Scripture but on Let’s Not Be Like Those People.
People are great at throwing babies out with bath water. In fact, sometimes we just throw out babies and keep bath water.
Churches throw out the baby (the Scripture) and keep the bath water (whatever drivel they decide to believe instead). Each assumes they are spiritual because spiritual maturity is mostly measured by comparison with other people. Since we’re Not Like Those People, we assume our not-likeness is where we are better, more mature, more right. Simply being better than others is good enough.
This is not growing into Christ though; this is just growing into being Not Like Those People.
We’ve reached a point where true uniqueness is a church that actually has Scripture as their authority. Does this church exist? I think it’s about impossible.
2,000 years of church arguing and factions has created an environment where it is very difficult to agree with any Christian anymore. Human philosophy, church and family tradition, and many other things have clouded our vision.
Is it possible for a church to have biblical doctrine? Maybe, but it’s highly doubtful. Is it possible for a person to? It’s more likely, but also very difficult.
How do you know if your doctrine is based on Scripture? Well, read the Bible a lot. Anytime a verse annoys you, pay attention, that’s probably where your doctrine is based on something else. If you read the Bible over and over, every time you should learn more, and it should slightly inform and change your doctrine.
If that’s not happening, then you aren’t paying attention. You’re simply reading the Bible and your brain is doing confirmation bias—it only notices verses that agree with your doctrine.
If you claim you’ve attentively read the Bible and didn’t change/modify any views, then you have to conclude you have 100% perfect doctrine. That’s quite the claim. I know people who get pretty close to claiming this and well, they don’t agree with each other on doctrine!
Read the Bible. Change your beliefs where necessary. Be part of a body of believers. Don’t isolate yourself. Hopefully you can at least find a church that has a couple humble people in it who truly want to grow and don’t think they’ve already arrived. You can help each other detect bias.
Please read your Bible. Over and over. Pay attention to context. Do the work.
But also know that knowledge puffs up. If you have all knowledge and have not love it profits you nothing. Doctrine is not simply for picking fights. It’s for informing your life and changing you into the person of Jesus Christ. And please try your hardest not to fall into the trap of “Not Being Like Those People.” Just follow Christ. Let Him change you.