I don't go around calling fellow believers false teachers. I might say I disagree. I try not to tear down.
We are all lacking to a point, but I wouldn't say that makes us all false teachers. I would rather say we are work in progress.
I believe the Scripture harmonizes to the full. That God speaks only truth and nothing but the truth, and can't contradict Himself because God is not the author of confusion. What is found in the Bible, is a
seeming contradiction of two things that are true simultaneously - it's called a
paradox. I believe God uses paradox in the Bible intentionally. To give us clues. When seeming "contradiction" is cleared up and explained - that's how to know you now understand correctly. Scriptures don't negate one another to make one side right and the other wrong, they work together, always, we might just not understand all at once.
Here's an example of a paradox: Gospel accounts disagreeing on the color of Jesus' robe after the arrest of Jesus. Was it purple, or scarlet? But the purple of that time was not a violet purple. It was a tyrian purple, a lot closer to red wine color. Biblical scarlet and purple were
similar, purple looked kind of like this, and it wasn't hard to confuse them, especially in dim light. Both colors are attributed to Jesus for prophetic reasons too, but I won't get into it now.
Paradox asks for trust in God and exercising patience until it's fully cleared up. But if someone wants to "be right" and argue, they will rush and pick a side before they really understand the matter. They don't care if it still contradicts. They want to believe they got it all figured out, and they received their wages, convinced they nailed it all down. It's very hard for some people to accept that maybe they are wrong about something, or maybe none of us are meant to figure certain things out until the end. Someone wrote, "You will only get as much from the truth as you're willing to put into it."