Jeremiah gives us a ‘heads up’ of the self-destructive foe inside all of us whether Christian or not: 

The heart is devious above all else; it is perverse—who can understand it? (Jer. 17.9) NET

For Christians it is not our only foe but probably the one we are the least aware of, hence, Jeremiah’s last clause “who can know it” (as in another translation). The point is that we operate mostly by what we observe to be threats to ourselves but miss ‘the old man’ (to use Paul’s reference) who insidiously tries to outrun and beat the New Creation inside of us as The Redeemed- see 1 Cor. 9.27 for the concept as Paul describes it. Here is an article that speaks to one aspect: prosperity.

“Men are undoubtedly more in danger from prosperity than from adversity. For when matters go smoothly, they flatter themselves and are intoxicated by their success.”⎯ John Calvin Commentary on Isaiah 32:11

Reflections by Todd Mangum, of Biblical Theological Seminary

If there was ever a group of people in history that needed to heed this point it is Americans today: American Christians especially.

It is a point that God warned His people about early on. It is as if God knows that people will turn to Him when they are under duress.  It is “when your cities are great and splendid,” “your houses are full of all good things,” when the “cisterns are hewn” and fresh water abounds, when “the vineyards and olive trees” are plump with their produce, “and you shall eat and be satisfied” – that is when “you must beware, lest you forget the LORD who brought you from the land of Egypt, out of the house of slavery” (Deut. 6:10-12; cf. Deut 8:11-14).

Isaiah the prophet drives home this very point in the 8^th century B.C., warning the people (my paraphrase) “YOU ARE FORGETTING! YOUR PROSPERITY IS MAKING YOU STUPID!”  This prophecy is what prompts Calvin’s observation in the 16^th century (more than 2,000 years later).  And 500 years after that, here we are, forgetful and stupid once again.

Jesus states plainly, “You cannot serve both God and materialism” (Matt. 6:24). It really does seem like many American Christians believe that if you work it right, you can. How forgetful, how stupid we are.

What would Calvin say about a country so prosperous, about a people so arrogant and proud, so comfortable and complacent? What would Isaiah say? What would Moses say?  What would Jesus say?  (I’m guessing the message would be similar and would be along the lines of: “Beware!  You are forgetting, and your prosperity is making you stupid!”)

So, what do we do?

Here’s what Calvin proposes in his commentary on this prophecy: “Tremble” (v. 11),  “Mourn” (v. 12) “Till the Spirit be poured out on you” (v. 15).

Love of money

Christians throughout the ages have recognized the value of spiritual disciplines – particularly such disciplines as fasting. Rhythms of these disciplines facilitate regular periods of focus on our walk and relationship with God and on our need for repentance. Christians of times past, perhaps much more than Christians living today’s fast-paced life of perpetual busyness, knew the importance of setting aside times when some aspect comforts and enjoyments were foresworn in order to remember and recalibrate. The Cross must be remembered and embraced, lest the glory of resurrection be considered simply an entitlement rather than a blessing following sacrificial faith.

Don’t we need such a season of fasting, of repentance in sackcloth and ashes, today more than ever?  Is it not time that our arrogant stupidity be rebuked with remembering the Lord our God and what He rightly demands of us and give Him the glory due His name? And due His name alone?

I prefer prosperity to adversity myself. But I cannot escape the truth of Calvin’s warning, rooted in the warnings of the prophets of old.  How about you?

Todd Mangum is the Lester and Kathryn Clemens Professor of Missional Theology  at Biblical Theological Seminary in Greater Philadelphia, PA.