Jeremiah 31:37

37 This is what the LORD says: “Only if the heavens above can be measured and the foundations of the earth below be searched out will I reject all the descendants of Israel because of all they have done,” declares the LORD.

Read Jeremiah 31:37 Using Other Translations

Thus saith the LORD; If heaven above can be measured, and the foundations of the earth searched out beneath, I will also cast off all the seed of Israel for all that they have done, saith the LORD.
Thus says the LORD: "If the heavens above can be measured, and the foundations of the earth below can be explored, then I will cast off all the offspring of Israel for all that they have done, declares the LORD."
This is what the LORD says: “Just as the heavens cannot be measured and the foundations of the earth cannot be explored, so I will not consider casting them away for the evil they have done. I, the LORD, have spoken!

What does Jeremiah 31:37 mean?

John Gill's Exposition of the Bible
Jeremiah 31:37

Thus saith the Lord, if heaven above can be measured
Either the space between the highest heavens and the earth; or the extent of the heavens, from one end of them to the other, which cannot be done by man; so the Targum,

``as it is impossible that man should know the measure of the heavens above;''
otherwise it is measured by the Lord, for he hath "meted out heaven with a span", ( Isaiah 40:12 ) ; and the foundations of the earth searched out beneath:
so as to be known what they are, or on what they are fastened, since the earth is hung upon nothing, ( Job 38:6 ) ( 26:7 ) ; I will also cast off all the seed of Israel for all that they have
done, saith the Lord;
as the former cannot be, so neither the latter; when there was a very great rejection of the Jews for their disbelief of the Messiah, they were not all cast off; the Apostle Paul was an instance to the contrary, and so were others: "the remnant according to the election of grace"; and there is a time coming when all Israel shall be saved, ( Romans 11:5 Romans 11:25 Romans 11:26 ) ; nor shall any of the spiritual Israel be cast off by him, or cast away from him, so as to perish; the Israel, whom God foreknew, is chosen, redeemed, and whom he calls by his grace; no, not for all the sins and transgressions they have been guilty of, however they may deserve it. The reasons are, because of his unchangeable love to them; his unalterable covenant with them; the satisfaction his son has made for them; and the free and full pardon of their sins, which he has granted to them.
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