I was going over some math homework with my son. He was frustrated that he was making simple mistakes in his math, and it cost him the right answer.
"In math, you don't get points for trying, you only get points for getting the right answer." I told him.
My mind immediately went to some missionary training I had when I was a youth. The director taught that you must get ALL of your doctrine 100% correct ALL of the time, or you'd not make it to heaven.
He used the following illustration:
"Suppose you're at a train station at lunch time, and your train leaves at 12:25pm. You look up at the clock and you see that the clock says it's 6:00pm. You know without a doubt that the clock is wrong, and begin searching for a new one." (He was alluding to false doctrines that are OBVIOUSLY wrong - how easy it is to discern and not be lead to hell in THAT handbasket.)
"But, let's suppose that the clock is only a few minutes off. It's four minutes slow. You may be inclined to trust that clock... but end up missing the train!"
(His illustration was meant to keep us alert to even the smallest error, lest we miss heaven due to a mistake.)
I took issue with that and challenged him in my very idealistic, naive 17 year old passionate way. We agreed to disagree.
But, all these years later... I wonder. Where's the grace, forgiveness and mercy in that? How can I possibly know ALL the correct doctrine ALL the time? Little old me? Is there room for God's mercy in my flawed understanding?
The scriptures say there is:

"Let me put it another way. The law was our guardian and teacher to lead us until Christ came. So now, though faith in Christ, we are made right with God. But now that faith in Christ has come, we no longer need the law as our guardian. So you you are all children of God through faith in Christ Jesus. And all who have been united with Christ in baptism have been made like him." (Galatians 3:24-26 NLT)

There's comfort in his grace.

And if my understanding of doctrine is as flawed as my understanding of mathematics... I'm grateful for that grace.

-Jennifer-