For they intended evil against you: they devised a mischievous act, which they are not able to perform.
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Augustine of Hippo
AD 430
12. "Because they turned evils against Thee." Now this punishment shall be recompensed to them, because the evils which they supposed to hang over them by Thy reign, they turned against Thee to Thy death. "They imagined a device, which they were not able to establish" (ver. 11). They imagined a device, saying, "It is expedient that one die for all:" which they were not able to establish, not knowing what they said.
Intended. Hebrew, "turned aside "like a torrent. The Ammonites had violated the law of nations, and had attempted to raise up very powerful enemies to invade David. (Calmet)
Establish. Hebrew leaves the sentence imperfect, to show the utter weakness or impotence of God's enemies. (Berthier)
