All the stuff we buy ends up eventually discarded. There’s no joy there. Our own bodies return to the dust. The things we think will make us happy are only temporary. But to be joined to the communion of Jesus and His Church – there is life, and light, and joy. Which is why John wants us to join not his church, but Christ’s Church. Being part of that one, holy, catholic and apostolic church is to enter into communion with the One who is Life. That’s our only path to joy. That’s why John, under the inspiration of the Holy Spirit, writes his Gospel and letters: “And we are writing these things so that our joy may be complete.”