Blessed are they that mourn: for they shall be comforted.
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Augustine of Hippo
Mourning is sorrow arising from the loss of things held dear; but those who are converted to God lose those things which they were accustomed to embrace as dear in this world: for they do not rejoice in those things in which they formerly rejoiced; and until the love of eternal things be in them, they are wounded by some measure of grief. Therefore they will be comforted by the Holy Spirit, who on this account chiefly is called the Paraclete, i.e. the Comforter, in order that, while losing the temporal joy, they may enjoy to the full that which is eternal.