22:3 serve him. Life in the new earth will be far more than mere rest and fellowship. There will be ample time for these also, as well as for harps and singing, but there will also be work to do. This work will no doubt be referenced in some appropriate way to our service here in this life (note Revelation 22:12), but will surely be satisfying and fruitful work. In an infinite universe, with an eternity of time, we can never run out of something to do!