It doesn't take long to discover that Christians don't agree on much of anything. You can find pro-choice and pro-life Christians, Christians who believe in the bodily resurrection of Jesus Christ and those who don't, Bible-believing Christians and Bible-critiquing Christians, pacifists and militarists, soul-winning missionaries and food-giving social justice activists. There are even Christians who don't believe in God!
All of these Christians draw on a combination of tradition, experience, Scripture and reason to explain the version of faith they find most compelling, most fitting, most true. Being the most compelling explanation of the faith apparently matters to most versions of Christianity. Tolerance for diversity of opinions doesn't often characterize theological discussions.
Certainly, some ideas about what it means to be Christian have less credibility in the larger Christian culture (mainstream Protestants and Catholics). Still, centuries of debate have gone into some of the core doctrines the (majority) church claims as inescapable, Holy Spirit-given truth.
One of the ways Christians manage the diversity of opinions is to reduce the faith to "five essentials" or the ancient creeds or the little 'o' orthodox core tenets. Then believers debate which ones those are, appealing to established authorities such as the Pope (RCC), tradition (EO), or the Bible (Protestants). All versions claim a connection with the early church and the Holy Spirit.
Since sharing a common view of essentials has mattered to the "church" for most of history, I often felt compelled to weigh theological arguments and decide between them (I didn't think much about who had the right to interpret as I did which interpretation made the most sense to me). I discovered early in my journey that "trying on" a viewpoint aloud (online especially) was dangerous to me and my business. I wasn't in "danger" as in 'at gunpoint', but rather, the questions I had and my attempts at answering them called my faith into question for communities who depended on shared faith statements.
By this time, I had read a ton of theology. The claims to certainty started to sound a little desperate to me (perhaps mirroring my own need to find a place to stand confidently). I asked myself: Why was there such a need to clamp down and require a perspective of fellow "believers" (or doubters)? Why must those in leadership state emphatically that an answer can be found or that a specific tradition has found it? I realized that I knew the answer to that question, though.
For instance, if one of the tenets most believers accept is that the Bible tells the true story of salvation, yet there are 15 different ideas about what that story is, the next step is to wonder how to interpret the Bible in order to arrive at the "right" answer. And of course, committing to an answer matters because things like where you live (America or abroad), how you spend time (winning souls or working in a job or raising your kids), how you spend money (donations to missions or soup kitchens), and how you treat "the lost" depend on how you answer this question. Even whether or not you believe in creationism versus evolution or how to think about miracles (do we pray for the sick expecting healing or not?) impact how you see reality, how you interact with it. These issues are not abstractions. I knew that how I lived my faith depended on the answers I believed.
So I changed the focus of my questions. I pulled back the lens and determined that doctrinal issues would fall into place if I found a reliable source of interpretation for the Bible and the tradition. Rather than asking which doctrines were truest or most correct, I decided to find out who had the best credentials to determine what those doctrines ought to be. Simple enough, right?