Isn’t it possible to be too happy? Don’t you ever encounter people who strike you as too happy? When I meet such people, I get the feeling that they are trying to sell me something. Maybe they are selling a product for a financial gain, or maybe they are selling some idea, or maybe they are selling an image of themselves.
Real happiness has to be rooted in some external reality. If Bill decides that he is going to be happy no matter what, then he is disconnecting his happiness from the world around him. It is better, I suggest, for Bill to be sad when the reality around him is sad, and be happy only when the reality around him is a happy one.
Christians know that the reality around them is, fundamentally, a happy one. Each and every one of us was created by a God who loves us and who sent his only son to redeem us. That is cause for deepest happiness, but we hold this happiness, this treasure, in earthen vessels (Cf. 2 Corinthians 4:7). In other words, we should not become too happy, because our happiness “comes from God and not from us” (Cf. 2 Corinthians 4:7). In fact, as long as we are on this earth, “we are afflicted in every way, but not constrained; perplexed, but not driven to despair; persecuted, but not abandoned; struck down, but not destroyed; always carrying about in the body the dying of Jesus, so that the life of Jesus may also be manifested in our body. For we who live are constantly being given up to death for the sake of Jesus, so that the life of Jesus may be manifested in our mortal flesh” (2 Corinthians 4:8-11).
Christian happiness is tempered by the sober reality of Christian suffering. If we would live with Jesus, we must die with him.