Romans 12:12, Rejoice in hope, be patient in tribulation, be constant in prayer.
Again, I borrow from Luther, who describes a twofold joy: “The first kind has to do with things that are visible, inwardly or outwardly. This kind is vain, because it is transitory. The other kind has to do with invisible things, that is, things that are unknown but simply accepted in faith; and this is true joy, eternal, firm, and without this kind of hope there is no joy in the other” (Lectures on Romans, LW 25:457).
Since I am writing in a different culture than Luther wrote, I would distinguish between happiness and joy. Happiness belongs to Luther’s first kind, and joy to his second. Thus, as I find myself saying often: Happiness is based on our circumstances, so it always changes; joy is based on the eternal hope we have in Jesus Christ.
Our culture—which is a common pattern among cultures in all ages—is obsessed with happiness, which it bases on possessions, wealth, social status, and autonomous living. Thus, no one is ever truly happy because the foundation of their happiness is built on sand (cf. Matthew 7:24-27), which is perennially shifting. Christ, however, is the rock, which never moves, for He is eternal.
Therefore, we can always rejoice—even in tribulation—because of the eternal hope we have in Christ. This is joy: rejoicing—celebrating—in Christ’s work of salvation, who baptises you with His Spirit through whom God the Father adopts you as His son or daughter (Galatians 3:26-29). It is from this joy alone that all earthly happiness finds its root.
Thus, I can rejoice that I have money not simply for money’s sake, but because God provided it so I may care for my family, my neighbour, and myself. I can rejoice in my hobbies because I take part in various communities in which I can love others as Christ has loved me. And so on.
Happiness is often selfish, but the joy of the Lord shapes and transforms our happiness because of the hope we have in Him, which is the sure hope that enables us to be patient in tribulation—when happiness/joy turns to sorrow—and to be constant in prayer for all our needs and the needs of others.