Charles Ellicott Commentary Malachi 4:6

"And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers; lest I come and smite the earth with a curse." — Malachi 4:6 (ASV)

And he shall turn ... to their fathers. —This does not refer to the settlement of family disputes, such as might have arisen from marriage with foreign wives.

“The fathers are rather the ancestors of the Israelitish nation, the patriarchs, and generally the pious forefathers ... The sons, or children, are the degenerate descendants of Malachi’s own time and the succeeding ages.” —Keil.

“The hearts of the godly fathers and ungodly sons are estranged from one another. The bond of union—namely, the common love of God—is lacking. The fathers are ashamed of their children, and the children of their fathers.” —Hengstenberg.

(Compare particularly to Isaiah 29:22-24, and the paraphrastic citation of Malachi 4:6 in Luke 1:17.)

Curse. —Better, ban. (Compare to Zechariah 14:11.) As with the conclusion of Isaiah, Lamentations, and Ecclesiastes, so here the Jew read in the synagogue the second to last verse again after the last verse, to avoid concluding with words of ill omen, thus: “Behold I send you Elijah the prophet before the coming of the great and dreadful day of JEHOVAH.”