Matthew Poole and continuators on Daniel 4:33

33 The same hour was the thing fulfilled upon Nebuchadnezzar; and he was driven from men , and did eat grass as oxen, and his body was wet with the dew of heaven, till his hairs were grown like eagles feathers, and his nails like birds claws .

Being bereft of his understanding, as a man distracted he fled, and betook himself to the woods, or was thrust and driven out either by popular tumults or conspiracy of his Nobles, or by his Son Evilmerodac, some think, when he raved he was bound with chains, and after turned off loose into the Woods among Beasts.

And his nailes like Birds claws, which might easily grow in seven years to a prodigious length and deformity.