Each beatitude builds upon the one before it. Jesus is not giving a random list of attitudes or deeds to perform. When we properly understand what Jesus is presenting in His great sermon it will have a profound affect on us. This is the second of the beatitudes.
“Blessed are they that mourn: for they shall be comforted.”
The Beatitudes are paradoxical. What could be more self-contradictory than the idea that the sad are happy and that the path to happiness is sadness. The way to rejoicing is in mourning. This is not what the world teaches. It teaches happiness is in pleasure. Money brings happiness, entertainment brings happiness, fame and praise brings happiness. But Jesus is speaking of another kind of mourning. It is a godly sorrow. A mourning that only those who sincerely desire to belong to Him have. Our happiness comes from our turning from sin and turning to God and receiving forgiveness.