What does Jeremiah 31:36 say would happen if the laws of nature depart?

Les explains that Jeremiah 31:35 first describes the Lord as the Creator who gives the sun for light by day and the ordinances of the moon and stars for light by night, dividing the sea when its waves roar, whose name is the Lord of hosts. Then verse 36 declares that if those ordinances—the laws of nature and science—depart from before Him, the seed of Israel would also cease from being a nation before Him forever. The passage continues that if heaven above can be measured and the foundations of the earth searched out beneath, then God would cast off the seed of Israel for all they have done. Les asks whether this can be done, answers it cannot, and concludes God will never cast aside Israel. He warns not to believe God is through with His chosen nation Israel. The problem arose when they rejected their Messiah and crucified Him, and Peter could not get them to believe in the early chapters of Acts. God then raised up Saul of Tarsus, known as Paul, and sent him primarily to the Gentiles, just as earlier He went primarily to the Jew. Les notes that as there were Gentile exceptions when God dealt with the Jew, there are individual Jews who can be saved in the age of grace. He also stresses that the church must not be mixed up with Israel in the tribulation, because that period is God's dealing with Israel, not the church, as Jeremiah 30:5 indicates.