In those days and at that time I will cause a righteous Branch to spring up for David, and he shall execute justice and righteousness in the land. In those days Judah will be saved and Jerusalem will dwell securely. And this is the name by which it will be called: ‘The Lord is our righteousness.’

Jeremiah 33:15, 16

The yes to all of God's promises is in Christ.
Here, we see Christ fulfilling God's covenant with David (2 Samuel 7). He "springs up" for David. He is from David, not a usurper. There were certainly unrighteous branches from David, but only Christ could be truly called a righteous Branch.
He "executes justice and righteousness in the land." Here is good government: he defends the innocent and punishes the guilty. He administers the Law.
And how do we, his subjects live? Are we miserable under this iron rule? "Judah will be saved." Note that it does not say Judah might be saved. Not Judah will be saved if they want. God does not leave our salvation to our fickleness and frailty. Judah will be saved. "Jerusalem will dwell securely." How do we live? We live in peace and happiness. Since we have been justified by faith, we have peace with God through our Lord Jesus Christ. (Romans 5:1) For the kingdom of God is not a matter of eating and drinking but of righteousness and peace and joy in the Holy Spirit. (Romans 14:17) And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus. (Philippians 4:7)
This peace is not always a physical peace, as our Lord said, "I have said these things to you, that in me you may have peace. In the world you will have tribulation. But take heart; I have overcome the world." (John 16:33)
"And this is the name by which it will be called: ‘The Lord is our righteousness.’" The Church will glory in the Lord her righteousness until she will become known by that title. And it is fitting that the bride should take her husband's name (Jeremiah 23:6).

Only in the Lord, it shall be said of me,
are righteousness and strength;

Isaiah 45:24a

God made Christ our wisdom and our righteousness and sanctification and redemption (1 Corinthians 1:30).
Through Christ, let us say Amen to God for his glory!