Isaiah 29:3,4 - Joseph Benson’s Commentary on the Old and New Testaments

And I will camp against thee, &c. That is, by those enemies whom I will assist and enable to take and destroy thee. The prophet may here refer to different sieges of Jerusalem, that of Sennacherib, that of the Chaldeans, or even to that of the Romans. Thou shalt be brought down thy speech shall be low Thou, who now speakest so loftily, shalt be humbled, and in a submissive manner, and with a low voice, shalt beg the favour of thine enemies. As of one that hath a familiar spirit, out of the ground “That the souls of the dead uttered a feeble, stridulous sound, very different from the natural human voice, was a popular notion among the heathen, as well as among the Jews. This appears from several passages of their poets, Homer, Virgil, Horace. The pretenders to the art of necromancy, who were chiefly women, had an art of speaking with a reigned voice, so as to deceive those who applied to them, by making them believe that it was the voice of the ghost. They had a way of uttering sounds, as if they were formed, not by the organs of speech, but deep in the chest, or in the belly, and were thence called εγγαστριμυθοι, ventriloqui. They could make the voice seem to come from beneath the ground, from a distant part, in another direction, and not from themselves, the better to impose upon those who consulted them. From these arts of the necromancers, the popular notion seems to have arisen that the ghost's voice was a weak, stridulous, almost an inarticulate sort of sound, very different from the speech of the living.” Bishop Lowth.