https://www.crossway.org/articles/the-doctrines-of-justification-and-union-with-christ-illuminate-one-another/

Jeremiah 31.31-34 promise to eradicate the Old Covenant by a better priesthood and law where all the members “know” the Lord, is set forth by the redemptive acts described in the text of the New Testament’s doctrines of vindication of Christ by the Spirit and our union with Him.