Author: David Wilber
I have a sincere challenge for flat earthers who insist that we must believe that the earth is flat "because the Bible says so." I'm not trying to sound arrogant, but I've brought up this point to flat earthers countless times, and nobody has given a sufficient answer. I don't think there is one. That’s why, in my experience, rather than actually deal with the logical implications of their hermeneutic, the typical “response” I’ve encountered from flat eathers is to side-step or try to deflect when this point is raised.
If you are a flat earther, I ask that you prayerfully consider this argument and receive it with the love intended.
Let's grant the premise that the authors of the Bible believed in a flat earth, and thus they described the earth in those terms in Scripture. Why would that entail that Christians today must believe the earth is flat? I see no reason we should. Let me explain.
The ancient authors of the Bible believed a lot of things that we would reject today. The Bible is made up of ancient writings written by an ancient people in an ancient culture. The fact that the perspective of these ancient authors sometimes conflicts with modern science doesn't mean that Scripture is "wrong." It just means that the Bible needs to be interpreted within its historical context. God chose to deliver His revelation to all mankind for all time through these ancient authors. As Dr. John Walton says, "Though that message transcends culture, the form it was given in is, to some extent, culture-bound.” 
For instance, the ancient authors of the Bible believed that the source of our intellectual activity is not our brain but our heart and entrails (Gen. 6:5; Psa. 26:2; Jer. 11:20; etc.). Hebrew doesn’t even have a word for “brain.” Moreover, they believed that our eyes generated their own light so we could see:
Pre-modern people tended to believe that the eyes contained a fire or light, and it was this fire or light that made seeing possible. Prov 15:30 speaks of the “light of the eyes” (מְאוֹר־עֵינַיִם) and Gen 48:10 speaks of the “eyes becoming dim” as indicating near blindness. In 2Sam 12:11, “broad daylight” is literally “the eyes of the sun” in the Hebrew (עֵינֵי הַשֶּׁמֶשׁ). It was not until c. 1500 CE that the eye was understood as collecting and focusing light. Up until that time, the belief was that the eye generated its own light. 
The authors wrote Scripture in these terms because that was their ancient understanding of the human body. We've since learned that the source of our intellectual activity is in our brain, not our entrails. We've also learned that the eye is a collector of light, not a generator of its own light. Many more examples could be cited.
In order for the flat earthist hermeneutic to be consistent, you must believe that we think with our entrails and that our eyes generate light. If you insist that we adopt the biblical authors' cosmology, why not also their physiology?
The reason you don't is you're smart enough to realize that the Bible doesn't demand that you adopt the physiology of the ancient biblical authors. Now take that a step further: Neither does the Bible demand you adopt ancient Israelite cosmology if, indeed, the ancient Israelites believed in a flat earth. But if you insist that we must believe in a flat earth, then in order to be consistent, you must also insist that we must believe we think with our entrails and our eyes emit light.
Flat earthers will inevitably declare, “But if you reject the cosmology of the authors of the Bible, then you can’t trust them on anything else!”
That assertion is flawed. Dr. Mike Heiser explains it better than I can:
God chose to communicate His message through ancient people who held to pre-scientific beliefs. He chose not to correct those beliefs because teaching correct science wasn’t the aim of Scripture. The aim of Scripture was to tell the Israelites, and everyone thereafter, who God was and what their relationship was with Him […] So even if parts of the Bible contain outdated information about the physical world, we can still trust it for the truths that God really wanted to communicate. 
Flat earthers often shriek, “But if God’s revelation contains outdated information, that makes God a liar!” Again, Heiser addresses this:
The first thing to realize is that God wasn’t the one who told people to believe unscientific things. God didn’t tell people the world was flat or that rain came through portals in the sky or that their liver, kidneys, or intestines were the seat of human intellect and emotion. Those views were already commonplace in the ancient world when God inspired Scripture through the people that He picked. The biblical authors were already part of that world. God wasn’t endorsing their beliefs; He decided to use people who held those beliefs. That was God’s decision. He didn’t mind because He knew the ancient writers could make the points He wanted them to make in their own way. 
God's goal was not to teach science. If it was, He would have corrected the scientific understandings of the ancient people whom He sovereignly chose to transmit His revelation. He didn't. The Message He wanted to transmit transcends culture and the science of their day and ours. His Word endures forever.
We are to rightly handle the word of truth (2 Tim. 2:15). Insisting that the Bible demands we believe that the earth is flat is a mishandling of God’s revelation to us. As I’ve written elsewhere, flat earthism is not only a mishandling of the biblical text but also a destructive error that hurts the body of Messiah and profanes the name of God. Turn from this foolish controversy and focus on what the Messiah and the apostles told us to focus on.
1. John H. Walton, Genesis: The NIV Application Commentary (Zondervan, Kindle Edition), p. 19.
2. Tim Hegg, Commentary on the Gospel of Matthew Chapters 1-7 (Tacoma, WA: TorahResource, 2007) , p. 254
3. Michael Heiser, Does the Bible Teach Science? How the Bible’s Own Context Answers the Question, https://youtu.be/5dFQR6MQ9es
About David Wilber
David is first and foremost a passionate follower of Yeshua the Messiah. He is also a writer, speaker, and teacher.
David’s heart is to minister to God’s people by helping them rediscover the validity and blessing of God’s Torah and help prepare them to give an answer to anyone who asks about the hope within them (1 Peter 3:15)…