Matthew
Matthew 5:4ESV·traditional attribution

“Blessed are those who mourn, for they shall be comforted.

John Calvin Reformed @genevareformer

4. Happy are they that mourn. This statement is closely connected with the preceding one, and is a sort of appendage or confirmation of it. The ordinary belief is, that calamities render a man unhappy. This arises from the consideration, that they constantly bring along with them mourning and grief. Now, nothing is supposed to be more inconsistent with happiness than mourning.

Matthew Henry Presbyterian @wholebiblehenry

Christ begins his sermon with blessings, for he came into the world to bless us (Act 3:26), as the great High Priest of our profession; as the blessed Melchizedec; as He in whom all the families of the earth should be blessed, Gen 12:3.

Commenting on Matthew 5:3-12

John Gill Reformed Baptist @doctorgill

Blessed are they that mourn,.... For sin, for their own sins; the sin of their nature, indwelling sin, which is always working in them, and is a continual grief of mind to them; the unbelief of their hearts, notwithstanding the many instances, declarations, promises, and discoveries of grace made unto them; their daily infirmities, and many sins of life, because they are committed against a...