Scribbling On the Back of an Old Envelope

EnvelopeIn the preface to his book, The Demon-Haunted World, Carl Sagan fondly recounts his college years, where he was able to learn from the minds of some of the 20th Century’s greatest minds, including astronomer G. P. Kuiper. He notes:

It was from Kuiper that I first got a feeling for what is called a back-of-the-envelope calculation: A possible explanation to a problem occurs to you, you pull out an old envelope, appeal to your knowledge of fundamental physics, scribble a few approximate equation on the envelope, substitute in likely numerical values, and see if your answer comes anywhere near explaining your problem. If not, you look for a different explanation. It cut through nonsense like a knife through butter.1

Although those thoughts were related to a scientific approach, it seemed to me that they were also completely applicable in the theological realm. Even though some spiritual concepts are "simple" to comprehend (or should be), Christians (especially our scholars) often spend the majority of their time trying to wrap the infinite with finite words. We want to be able to explain exactly how salvation works, how God is both three and one, how Jesus was 100% human and 100% divine—the list goes on ad infinitum. Although there is much that can be elucidated, frequently we seem to be trying to describe the indescribable.

And we are no more successful at doing that then counting all the grains of sand on a beach or the stars in the sky.

However, we can learn from Kuiper and Sagan and when we come up with a possible solution for a theological conundrum we can pull out an old envelope, appeal to our knowledge of the Bible and God, scribble a few approximate ideas on the envelope, substitute in that which the Lord has show us before, and see if it comes anywhere near explaining our problem. If not, we can look for a different explanation.

And, I suspect, if we took this approach we could cut through a lot of theological nonsense like a knife through butter—whether it be our own balderdash or someone else’s.

The reason this is true is that one of the fundamental "truths" about truth is that it cannot contradict itself. So, when you stick an axiomatic doctrine into your fancy new "equation" if, say, the Father is not as kind as the Son, then look for a different explanation. (Otherwise, Jesus was lying when in John 14:9 He assured Philip that "whoever has seen me has seen the Father."2 This fact alone makes a lot of soteriological explanations suspect…for instance, if they have the Son pleading with the Father to let us through the Pearly Gates).

Sagan’s book is about healthy scientific skepticism, and the Universal Church could use a lot of healthy doctrinal skepticism. Beyond inherently contradictory systematic theologies, much of what Christians hold as truth is based on very little evidence, tradition instead of the Word, or because of cultural and societal pressures (and not always from outside the church walls). We do not believe X because we’ve truly studied it for ourselves—and we’d never be able to defend it—especially to an "unhealthy" skeptic who is likely well-armed with a list of perceived shortcomings in our worldview.

Although I still strongly stand behind the words of Walt Allmand that we should "doubt [our] doubts before [we] doubt [our] beliefs,"3 perhaps it time for all of us to review the views that comprise our systematic theology and ask ourselves if we have come to that conclusion based on our own study (through all 66 books), or would it make sense for us to spend a bit more time looking at X, Y, and Z? However, the point of this article is less to question that which we’ve already been shown by our Lord than to encourage a healthy skepticism that will help keep us from following false teachers going forward (or becoming one ourselves).

As Solomon notes in Ecclesiastes 1:9, there really is nothing new under sun, whether it be truth or heresy4—so be especially skeptical of "new" light.

Be like the the Bereans and "[receive] the word with all eagerness, [and examine] the Scriptures daily to see if these things [are] so" (Acts 17:10).

Be like Kuiper and Sagan and look for a different solution when your equation doesn’t come anywhere near explaining your problem (but you can’t do that if you never even check).

Be like Christ and represent God accurately in your words and actions…and in your theology.

1 Sagan, A. (1997). The Demon-Haunted World (xiv). Balantine Books.

2 All Scripture references are from the English Standard Version.

3 Tan, P. L. (1996). Encyclopedia of 7700 illustrations : A treasury of illustrations, anecdotes, facts and quotations for pastors, teachers and Christian workers. Garland TX: Bible Communications.

4 In Ecclesiastes 1:9 Solomon is actually speaking about how history repeats itself, but his "there is nothing new under the sun" is applicable beyond that.

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Alan is an ordinary guy, living in a small, high plains Colorado town...and humbled to be a minister of God...

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