Blessed are those who mourn, for they will be comforted.
The word "blessed" means "happy, to be envied!" How strange that Jesus is saying in effect: How happy are the unhappy.
Mourning is often seen by the world as something to escape from. The human soul desires peace, ease, and joy. None of these are bad. Life should be joyful. But true joy does not come from anything outside of God. True peace, ease, and joy come from God.
Oftentimes, we humans look up at those who seem carefree or those who are actually without care. When we see the rich, we say "what a good life they have! how blessed they are!"
To live an unhappy life is a hard thing. Those who mourn often wonder if God has forgotten them, or if God is against them. They often are judged by the world. Which only makes their unhappiness worse.
Perhaps they are poor, suffering with ill health, cruel neighbors, sick children. God is able to restore a person's life and to remove all these ailments. The kingdom of God and the gospel provides for restoration, healing, and joy. Sometimes sorrows are less tangible and is a world-weariness or a lingerng grief. Some people are unhappy all their lives even if there are no external reasons for their sorrow. Whatever the cause, some sorrows cannot be cured on earth. In fact, some sorrows are caused by the very fact that we are on earth. The world often tries to forget that the world is fallen. They will say for instance that death is "part of the cycle of life" and that God made death or reincarnation. But Christians know that death is not a good thing. It is a curse. Instinctively, we know we are not made to die. We know we are not made to be separated from others. Instinctively we feel the smallness of the world's joys.
The gospel is good news to such people. It brings the good news that in many ways we can triumph over the sorrows that have befallen humans since the fall of man. The gospel brings the comfort the mourners have been seeking. The gospel has joyous healing comforting earthly blessings but also comfort for those who long for heaven. After all, we are given God's Holy Spirit, which is a foretaste of the riches and blessings of heaven.
But just because there is healing and new life and even riches in the gospel it doesn't necessarily say that we should use the gospel to get rich. Some people mix up the blessings of the gospel with the desire for wealth. But the gospel has a joy that is always connected with mourning. Always, always, Christians long for God, righteousness, and heaven, our true home. Christians long for their true selves, when we are clothed with God's own righteousness.