Blessed are they that mourn: for they shall be comforted.
All Commentaries on Matthew 5:4 Go To Matthew 5
Jerome
AD 420
For the mourning here meant is not for the dead by common course of nature, but for the dead in sins, and vices. Thus Samuel mourned for Saul, thus the Apostle Paul mourned for those who had not performed penance after uncleanness.
