John Trapp on Isaiah 29:4

Ver. 4. And thou ſhalt be brought down] from thoſe lofty pinacles of ſelf exaltation, whereunto thy pride hath peirhed thee.

And ſpeak out of the ground] humillime & ſubmiſſime, thou ſhalt ſpeak ſupplicatione, with a low voice, as broken men, who waſt wont to face the heavens, and ſpeak in ſpite of God and men, ſpeak big words, bubbles of words: See Jer. 46.22.

And thy voice ſhall be as one that hath a familiar ſpirit] cujus vox eſt gracilis, flebilis, hiulca, confuſa, gemebunda.

Out of the ground] as the Devil at Delphos did.