Although the LORD has spoken through the prophets including Jeremiah to bring Jerusalem to justice by sword, famine and plague under the hands of the king of Babylon
Nonetheless, God would again gather the Israelites from the lands he has scattered them in his anger
He would bring them back to live in safety, even secure enough that their one-time desolate land on account of their sin, would sell legally for farmlands
This time, the LORD would be their God, and they would be His people. He would give them one heart and purpose: to worship God forever
After their punishment, God would again usher in a wonderful life of prosperity
God would make a covenant with them, a new relationship in which He will constantly bless them, and they will constantly serve God.
In the second lesson, the author of Hebrews made a direct reference to the promise of a New Covenant as declared through Jeremiah (31:31-34)
This was because God saw fault in the first Covenant as well as in the people
The first Covenant was limited in its intent and effectiveness, it was provisional.
Likewise, the people were unfaithful to the Covenant, so God turned His back.
Jeremiah looked forward to the day when God would establish this New Covenant with the people of Israel and Judah, making the first one obsolete
This time, God will put His law (the law of the Spirit) in their minds and write them on their hearts, He will be their God, and they will be His people
They will not need teach relatives and neighbors to know God, for God would make everyone to know Him, even from the least to the greatest
This New Covenant promises full and eternal forgiveness, which the Mosaic order could not accomplish but Jesus has provided in full.