Albert Barnes Commentary Zephaniah 1:9

"And in that day I will punish all those that leap over the threshold, that fill their master`s house with violence and deceit." — Zephaniah 1:9 (ASV)

I will punish all those that leap on the threshold – Neither language, history, nor context allows this to be understood as the idolatrous custom of Ashdod, not to tread on the threshold of the temple of Dagon. It would indeed have been a strange infatuation of idolatry for God’s people to adopt an act of superstitious reverence for an idol in the very instance when its nothingness and the power of the true God had been shown.

Indeed, nothing is too brutish for one who chooses an idol instead of the true God, preferring Satan to the good God. Yet, the superstition apparently belonged to Ashdod alone. The worship of Dagon, although another form of untrue worship, does not appear, like that of Baal, to have fascinated the Jews. Nor would Zephaniah, to express a rare superstition, have chosen an idiom that might more readily express the contrary: that they leapt on the threshold, not over it.

They are also the same persons who leap on the threshold and who fill their masters’ houses with violence and deceit. Yet, this relates not to superstition, but to plunder and goods unjustly gotten. Just as he previously declared God’s judgments on idolatry, so he does here on sins against the second table, whether by open violence or secret fraud, as do also Habakkuk (Habakkuk 1:2–3) and Jeremiah (Jeremiah 5:27). All of this—whether open or hidden from man, every wrongful dealing (for every sin regarding a neighbor’s goods falls under these two, violence or fraud)—will be avenged in that day.

Here again, all that remains is the sin. They enriched, as they thought, their masters by cunning or by force; they schemed, plotted, robbed; they succeeded to their heart’s desire. But, ill-gotten, ill-spent! They filled their masters’ houses quite full; but with what? With violence and deceit, which witnessed against them and brought down the judgments of God on them.