Restorers

And they that shall be of thee shall build the old waste places: thou shalt raise up the foundations of many generations; and thou shalt be called, The repairer of the breach, The restorer of paths to dwell in. (Isaiah 58:12)

For the Lord shall comfort Zion: he will comfort all her waste places; and he will make her wilderness like Eden, and her desert like the garden of the Lord; joy and gladness shall be found therein, thanksgiving, and the voice of melody. (Isaiah 51:3)

Break forth into joy, sing together, ye waste places of Jerusalem: for the Lord hath comforted his people, he hath redeemed Jerusalem. (Isaiah 52:9)

When will the deserts become a paradise? At the very end, after Jesus has returned (Rev 21:1). It that what is meant in Isaiah 58 by building the old waste places? I don't know. The restoration of the character of God in his once-wasted people will happen just before his return, perhaps this is the old waste places. Isaiah 58 is describing a situation before the Second Advent, not after it.
Jesus wants to restore things that have been destroyed as a consequence of sin. He is not the author of emptiness, but fulfilment. If he can command us to sing in joy he can give us the ability to do it. Trust in the Lord like you don't trust anything else, and he will fill your heart with joy.