I've never had to convince anyone that joy is good, but sorrow is a tougher sell. Sometimes we Christians describe a life following Jesus as something straight out of the pages of a pretty magazine. The house is beautiful, the kids have clean faces and matching socks, the refrigerator is full. We confuse the favor of God with the benefits of living in a blessed country during an era of relative prosperity. However, the words of Jesus himself in John 16:33, "In this world you will have trouble," defy the idea of a picture-perfect existence in our preeternal world.
The Bible doesn't run from sorrow, but rather encourages us to see it as one of the blessings born on the battlefield. I have experienced at least three distinctly beautiful benefits from sorrow.
1) Sorrow connects us to the comfort of God's presence.
The Sermon on the Mount is Jesus's most extensive monologue, and is the best foundation we have on which to build a theology about the blessing and favor of God. In it, he mentions eight specific "blessings," including poverty, hunger, and persecution. One has grown near and dear to my heart: "Blessed are those who mourn, for they shall be comforted" (Matthew 5:4).
I realize that comfort seems like a cheap consolation prize for mourning. It's like, "Blessed are those who break their arm, for they shall get a shiny new cast!" This promise, however, is so much bigger and better than that.