"Sing, O daughter of Zion! Shout, O Israel! Be glad and rejoice with all your heart, O daughter of Jerusalem! The LORD has taken away your judgments, He has cast out your enemy. The King of Israel, the LORD, is in your midst; You shall see disaster no more. In that day it shall be said to Jerusalem: 'Do not fear; Zion, let not your hands be weak. The LORD your God in your midst, The Mighty One, will save; He will rejoice over you with gladness, He will quiet you with His love, He will rejoice over you with singing.'"
God calls us to sing, because He has dismissed our case from His court. Our guilt and our accuser are put away forever. And as He steps down from the bench He leads us from the courtroom to a grand reception with a feast laid for us. He washes us, strengthens us, clothes us, heals us, exalts us, all as He sings over us with His joy. Jesus knew all this, and was doing it, as He sang a hymn with His disciples at Passover and then went to
Gethsemane and Golgotha. He leads us in worship of God the Father, singing over those he has redeemed, and also singing the psalms as a faithful son of God.