Albert Barnes Commentary Joel 1:3

"Tell ye your children of it, and [let] your children [tell] their children, and their children another generation." — Joel 1:3 (ASV)

Tell your children of it - In the order of God’s goodness, generation was to declare to generation the wonders of His love. He established a testimony in Jacob and appointed a law in Israel, which He commanded our fathers that they should make them known to their children, that the generation to come might know them—the children who should be born, who should arise and declare them to their children, that they might ... not forget the works of God (Psalms 78:5–7). This tradition of thankful memories, God, as the Psalmist says, enforced in the law: Take heed to yourself, lest you forget the things which your eyes have seen, but teach them to your sons and your sons’ sons (Deuteronomy 4:9; Deuteronomy 11:19).

This was the purpose of the memorial acts of the ritual: that their sons might inquire about their meaning, and that fathers might tell them of God’s wonders (Deuteronomy 6:20–24). Now conversely, they are, from generation to generation, to tell this message of unheard-of woe and judgment concerning it. The memory of God’s deeds of love should have stirred them to gratitude; now He transmits to them memories of woe, so that they might plead with God concerning them and abandon the sins that bring them about.