Blessed are those who Mourn
Matthew 5:4 (ESV) … “Blessed are those who mourn, for they shall be comforted.”
If it be possible. If it can be done. This expression implies that it could not always be done. Still it should be an object of desire; and we should endeavour to obtain it.
In another seeming contradiction in terms, Jesus explained that those who mourn are blessed. Jesus reminded his disciples that the prophet Isaiah had promised that the Messiah would “comfort all who mourn” (Isaiah 61:2 niv). Scholars differ on the exact nature of this mourning. Some say that Jesus was referring to the nation of Israel mourning for its sins; others interpret this more personally, explaining that it refers to those who mourn for their own sins or even for personal grief or oppression. Tied with the beatitude in verse 3, this means that humility (realization of one’s unworthiness before God) also requires sorrow for sins. Still other scholars see in the word mourning a picture of God’s people who suffer because of their faith in him.
Whether Jesus’ followers mourn for sin or in suffering, God’s promise is sure—they will be comforted. Only God can take away sorrow for sin; only God can forgive and erase it. Only God can give comfort to those who suffer for his sake because they know their reward in the kingdom. There he will “wipe away every tear from their eyes” (Revelation 7:17 niv). Jesus explained to his disciples that following him would not involve fame, popularity, and wealth. Instead, it could very well mean sorrow, mourning, and suffering. But they would always know that God would be their comfort.[1]

[1] Barton, B. B. (1996). Matthew (p. 77). Tyndale House Publishers.