Some translations set poetry farther to the right than the rest of the text to show that it is poetry. The ULB does this with the poetry in 31:1-6, 8-22, 35-37.
This chapter begins with a transition from the previous chapter. "At that time" is a reference to the day of restoration mentioned in [Jeremiah 30:24](../../jer/30/24.md). (See: [[rc://en/tw/dict/bible/kt/restore]])
This chapter is an important teaching regarding the new covenant. God will make a new covenant that will bring forgiveness of sins and a desire to obey God. Scholars disagree about whether this new covenant has begun. (See: [[rc://en/tw/dict/bible/kt/covenant]] and [[rc://en/tw/dict/bible/kt/forgive]] and [[rc://en/tw/dict/bible/kt/sin]])
In this chapter, Jeremiah uses the term "Israel" in reference to the nation of Israel as a whole. He also uses it in reference to the northern kingdom of Israel and their people group.