“Blessed are they that mourn; for they shall be comforted” (Matt 5:4).
“They who weep for their own sins are blessed, but much more so who weep for others’ sins.” -Pseudo-Chrysostom
“The mourning here meant is not for the dead by common course of nature, but for the dead in sins, and vices.” -St. Jerome
“The comfort of mourners is the ceasing of their mourning; they then who mourn their own sins shall be consoled when they have received remittance thereof.” -Pseudo-Chrysostom
“God’s mercies are always greater than our troubles.” -St. John Chrysostom
“Mourning is sorrow for the loss of what is dear; but those that are turned to God lose the things that they held dear in this world; and as they have now no longer any joy in such things as before they had joy in, their sorrow may not be healed till there is formed within them a love of eternal things. They shall then be comforted by the Holy Spirit, who is therefore chiefly called, The Paraclete, that is, ‘Comforter’; so that for the loss of their temporal joys, they shall gain eternal joys.” -St. Augustine
“By mourning, two kinds of sorrow are intended; one for the miseries of this world, one for lack of heavenly things. . . . This kind of mourning none have but the poor and the meek, who as not loving the world acknowledge themselves miserable, and therefore desire heaven. Suitably, therefore, consolation is promised to them that mourn, that he who has sorrow at this present may have joy hereafter.” -Glossa apud Anselm
Quotations from St. Thomas Aquinas, Catena Aurea: Commentary on the Four Gospels Collected Out of the Works of the Fathers, Vol. I, Part I (Oxford: John Henry Parker, 1841).