they absolutely come from Scripture
(Jer 31:35 KJV) Thus saith the LORD, which giveth the sun for a light by day, and the ordinances of the moon and of the stars for a light by night, which divideth the sea when the waves thereof roar; The LORD of hosts is his name:
(Jer 31:36 KJV) If those ordinances depart from before me, saith the LORD, then the seed of Israel also shall cease from being a nation before me for ever.
(Jer 31:37 KJV) 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.
Paul makes clear in Gal 6:16 that the fulfillment of Israel is the church. So Jeremiah's prophecies here are fulfilled in the church, not the geographical country. The geographical country will not last forever; the church will.