In vain have I smitten your children,.... Or, "for vanity" ; for vain speaking, for making vain oaths and vows; so it is explained in the Talmud ; but the sense is, that the rod of chastisement was used in vain; the afflictions that came upon them had no effect on them to amend and reform them; they were never the better for them:they received no correction; or instruction by them; see Jer 5:3,your own sword hath devoured your prophets; as Isaiah, Zechariah, and Uriah, who were sent to them to reprove and correct them, but they were so far from receiving their correction, that they put them to death; though Kimchi mentions it as the sense of his father, and which he approves of, that this is to be understood, not of the true prophets of the Lord, but of false prophets; wherefore it is said, "your prophets"; and they had no prophets but false prophets, whose prophecy was the cause of the destruction of souls, and this brought ruin upon the prophets themselves; and this sense of the words Jerom gives into; it follows:like a destroying lion; that is, the sword of the Lord, according to the latter sense; the judgments of God, by which the people fall, and their false prophets with them, were like a lion that destroys and devours all that come near it.
The Septuagint and Arabic versions add,and ye were not afraid; which confirms what was before said, that chastisement and correction were in vain. awvl "propter vanitatem, [sive] vaniloquentiam", Vatablus.
T. Bab. Sabbat, fol. 32. 2. & Cetubot, fol. 72.