Who determines the main tenets and on what authority? What if another disagrees on something like salvation by election?
All good catechisms are rooted in scripture. If it's really good it will have more than one.
What if another disagrees on something like salvation by election?
Before someone disagrees to a catechism, they better have a good answer to the scriptures supporting it. I honestly know where someone is coming from when they say, "Well, that's a mystery..." to a doctrine. I could never understand Romans or the book of John. It didn't make sense. So that is what I often said when I couldn't reconcile a piece of scripture or these books. "I guess it's a mystery and I'll find out when I get to heaven."
Here's a secret from a relatively new Reformer. Reformers aren't arrogant although they might seem like it. They simply are reading the scriptures in their entirety. The problem is others are not and they don't want to reconcile the differences because it will affect their preconcieved notions.
Where I think people are on shakey ground is when they will argue with a clear piece of scripture with a, "Ya but....". They are not thinking about what the scripture is trying to teach them.