Who whet their tongue like a sword,.... Use cutting, wounding, killing, and devouring words; on which they set an edge, and make them keener and keener to hurt and ruin the characters and reputations of good men, and grieve and distress their minds;[and] bend [their bows to shoot] their arrows, [even] bitter words; such are the these doctrines of heretical men, which are roots of bitterness, that defile some and trouble others; such are the oaths and curses of profane sinners, whose mouths are full of cursing and bitterness; and such are the blasphemies of antichrist against God, against his tabernacle, and against them that dwell therein; and such are the hard speeches spoken by ungodly sinners against Christ and his people; these are like arrows shot from a bow, and full of deadly poison.
The Targum is"they stretch out their bows, they anoint their arrows with deadly and bitter poison.''There seems to be an allusion to fixing letters in arrows, and so shooting or directing them where it was desired they should fall and be taken up; so Timoxenus and Artobazus sent letters to one another in this way, at the siege of Potidaea : and after the same manner, the Jews say , Shebna and Joab sent letters to Sennacherib, acquainting him that all Israel were willing to make peace with him; but Hezekiah and Isaiah would not allow them to.
Herodot. Urania, sive l. 8. c. 128. Derash R. Aba in Kimchi in Psal. xi.