What makes a fundamentalist think that their interpretation of the Bible is the one and true interpretation?
They have the Holy Spirit who confirms His presense with them. We have a relationship with Jesus, the Father and the Holy Spirit. It is not just about knowledge of the truth, it is about a relationship.
An orphan can read about their father who really love thems but was separated from them at birth. Many people can come alongside this orphan who know his father and tell them all about his life, what a good man he was but it is just a story to the orphan that he doesn't really believe, because he hasn't seen him or talked to him.m or felt his love. Then one day, he shows up. His father demonstrates his love and the boy receives it with open arms, a dream that he always had, was now answered. They commune together and the boy learns all about his father.
This reminds me of that movie, "August Rush" love it.
Are they not acting as if they are God themselves when they assume that their interpretation must be infallible?
Well yes, in a way. God lives in us so we are ONE. We think his thoughts, He gives us truth and we just share it. God speaks through us ... at times. Now there are mixed signals too, things we think are comingbfrom God that are not things we are confused about. Go dgoces us bits and pieces butbnot full knowledge from day one. We must study, pray and in time learn. Certain truths of the Bible we don't get right away because we are not ready. God must first bring us through experiences for us to learn from, experiences where tuat scripture is mire applicable. Experience is key. Billy Graham said some scriptures he read a hundred times and onlybreceived a superficial basic understanding until decades later, a light went on when he received a deeper spiritual meaning that God gave him. Spiritual growth takes time.
how does it make any sense for a believer to say they don’t know what the future holds, but then turn around and say that you will come before God, in the future of course, after you die?
Events in the Bible pertaining to the future are certain to happen. Some Christians have little understanding of the scriptures and others have much. We are on all different levels, learning and growing in our faith. And faith is a gift, so according to God's purpose for a person's life, He gives and equips some for great things and the some just enough to get in the door. Many things outside of scripture are the same. Some people are very knowledgable and some are not.
As Christians, most of us know the fundamentals and si we can be certain about those, the essentuals. But there are non-essentials, doctrines that we argue about, are unsure of and hense divisions form within the body.
Therebis one life, one death and then the judgment. So in the end all come before God and are judged. Christians have been forgiven theor sins so will not be judged for sin. They will be judged concernings rewards for their service and howbthey used the gifts God gave them.
Also, how can a believer know anything at all when they say, “Only God knows”?
That statement is subjective. Again some people know lots but still in certain areas and circumstances, the details concerning events not written in the Bible, we can only say, Only God Knows.