--Samuel Rutherford
Have you ever been happy because someone you love is happy? You so identify with them that you enter into their delight and victory.
That's what Rutherford means, I think, when he speaks of our joy "because Christ sings." We are in Him, the Scriptures say. His death, burial, and resurrection become ours. And it is His joy that is our strength (cf. Nehemiah 8:10).
Pursuing Him, we may enter His victory and that brings joy. By faith to see the satisfaction in His eyes, to feel Him full of power and triumph, to know He knows He has won everything and that everyone He loves will come home and be with Him forever - there is joy.
The hollow alternative is to look for joy somewhere else: the fleeting affirmations of others, the pleasures of the flesh, our own temporary successes. In the end this is the way of despair.
I would rather try, and pray He gives me a greater vision, to see the light of His face, to imagine His voice like thunder, to settle in with all the great and small, the rulers and kings and shepherds and shopkeepers and soldiers and construction workers and single moms and little kids, to adore Him together, with never a thought of any glory but His. O, what joy, to shout and sing and laugh and clap and whistle and stomp and pray, all together: Worthy is the Lamb!
