His Righteousness is Our Peace (Our Everything)

"And the work of righteousness shall be peace; and the effect of righteousness quietness and assurance for ever." (Isaiah 32: 17) 

Righteousness is a gift (Romans 5: 17) which we are called to keep receiving. This gift is accorded to us because we have received His righteousness, His perfect standing:

"For he hath made him to be sin for us, who knew no sin; that we might be made the righteousness of God in him." (2 Corinthians 5: 21)

This righteousness allows us to receive His peace and joy:

"1Therefore being justified by faith, we have peace with God through our Lord Jesus Christ: 2By whom also we have access by faith into this grace wherein we stand, and rejoice in hope of the glory of God." (Romans 5: 1-2)

and

"14For he is our peace, who hath made both one, and hath broken down the middle wall of partition between us;" (Ephesians 2: 14)

Paul then explains to us how exactly Jesus is our peace:

"15Having abolished in his flesh the enmity, even the law of commandments contained in ordinances; for to make in himself of twain one new man, so making peace; 16And that he might reconcile both unto God in one body by the cross, having slain the enmity thereby:" (Ephesians 2: 15-16)

We have been reconciled to God the Father through Jesus Christ, who died on the Cross for our sins and granted us His perfect righteousness (cf. 2 Corinthians 5: 17-20)

This peace is established through the New Covenant, which grants us His righteousness:

"20Now the God of peace, that brought again from the dead our Lord Jesus, that great shepherd of the sheep, through the blood of the everlasting covenant, 21Make you perfect in every good work to do his will, working in you that which is wellpleasing in his sight, through Jesus Christ; to whom be glory for ever and ever. Amen." (Hebrews 13: 20-21)