Adolph Schlatter said of Friedrich Nietzsche:
The chief impression that I internalized from his lectures arose from his offensive haughtiness. He treated his listeners like despicable peons. He convinced me of the principle that to throw out love is to despoil the business of teaching—only genuine love can really educate.
Nietzsche believed in the superman, made by energy, intellect, and pride (Durant, The Story of Philosophy, 425–27). No energy can propel perfect righteousness, and no amount of energy will enable one to escape God. No intellect can recreate the universe, and no intellect will devise a way to avoid judgment. No pride fails to offend, and no pride will go un-humbled.
We will not be delivered by energy, intellect, and pride. We will be delivered if we repent of our sin and trust in Jesus.
God rejects those who will not repent.
Jeremiah 1 presents the calling of Jeremiah as a prophet like Moses. He indicted Israel’s spiritual adultery in chapter 2, called them to repent and be restored in 3:1–4:4, summoned them to wash their hearts from evil in 4:5–31, only to see Israel refuse to repent in chapter 5, which results in the verdict that Israel has been refined in vain and rejected in chapter 6.
The “Thus says the LORD” statements and the changes in theme structure this passage.
6:1–5, Looming Disaster
6:6–15, The Lord Announces Israel’s Punishment
6:6–8, Hearts That Keep Evil Fresh
6:9–15, Uncircumcised Ears
6:16–21, Israel Rejected Ancient Paths and Watchmen
6:22–26, The Lord Describes the Coming Enemy
6:27–30, Jeremiah the Tester of Metals
There are a number of similarities of language and thought between Jeremiah 1:18–19 and 6:27–30. In both places the LORD says to Jeremiah, “I have made you . . .” and the term rendered “tester of metals” in 6:27 in the ESV has the same consonants as the term rendered “fortified” in 1:18, and then in both places there are references to iron, bronze, and conflict between Jeremiah and the people.
All this leads me to think that after the introductory chapter that presents Jeremiah’s call (Jer 1), 1:18–6:30 is the first major section of Jeremiah’s book, a section bracketed by 1:18–19 and 6:27–30.
Sometimes people talk and write as though the book of Jeremiah is a sort of loose collection of sermon notes or transcriptions. I’m inclined to think, rather, that Jeremiah is a carefully arranged, carefully structured, finished literary product.
On October 30, 2011, it was my privilege to preach Jeremiah 6: Refined in Vain and Rejected at Kenwood Baptist Church.
 Werner Neuer, Adolf Schlatter: A Biography of Germany’s Premier Biblical Theologian, 1st ed. (Grand Rapids, Mich: Baker Books, 1996), 44.