Jeremiah 3

In comparing Judah as the Lord's wife, Jeremiah chastises Judah telling them -

"...thou hast played the harlot with many lovers..."  (Old Testament | Jeremiah 3:1)

Suggesting to me, spiritual and immoral adultery as those chose to forsake their covenants and follow idols and wickedness.  Because of that, Jeremiah asks Judah, have they not observed the wickedness of their sister kingdom, Israel and what happened to them saying -

"Hast thou seen that which backsliding Israel hath done? she is gone up upon every high mountain and under every green tree, and there hath played the harlot.
7 And I said after she had done all these things, Turn thou unto me. But she returned not. And her treacherous sister Judah saw it.
8 And I saw, when for all the causes whereby backsliding Israel committed adultery I had put her away, and given her a bill of divorce; yet her treacherous sister Judah feared not, but went and played the harlot also.
9 And it came to pass through the lightness of her whoredom, that she defiled the land, and committed adultery with stones and with stocks.
10 And yet for all this her treacherous sister Judah hath not turned unto me with her whole heart, but feignedly, saith the LORD.
11 And the LORD said unto me, The backsliding Israel hath justified herself more than treacherous Judah."  (Old Testament | Jeremiah 3:6 - 11)

We are taught over and over that history repeats itself.  This is will with Judah.  As he chastises Judah, Jeremiah turns to the gathering of Israel (and Judah) in latter days saying -

"Go and proclaim these words toward the north, and say, Return, thou backsliding Israel, saith the LORD; and I will not cause mine anger to fall upon you: for I am merciful, saith the LORD, and I will not keep anger for ever.
13 Only acknowledge thine iniquity, that thou hast transgressed against the LORD thy God, and hast scattered thy ways to the strangers under every green tree, and ye have not obeyed my voice, saith the LORD.
14 Turn, O backsliding children, saith the LORD; for I am married unto you: and I will take you one of a city, and two of a family, and I will bring you to Zion:
15 And I will give you pastors according to mine heart, which shall feed you with knowledge and understanding."  (Old Testament | Jeremiah 3:12 - 15)

And -

"At that time they shall call Jerusalem the throne of the LORD; and all the nations shall be gathered unto it, to the name of the LORD, to Jerusalem: neither shall they walk any more after the imagination of their evil heart.
18 In those days the house of Judah shall walk with the house of Israel, and they shall come together out of the land of the north to the land that I have given for an inheritance unto your fathers.
19 But I said, How shall I put thee among the children, and give thee a pleasant land, a goodly heritage of the hosts of nations? and I said, Thou shalt call me, My father; and shalt not turn away from me."  (Old Testament | Jeremiah 3:17 - 19)

In other words, covenants with the Lord will be entered into, obeyed and kept.