Matthew Poole and continuators on Daniel 5:19

19 And for the majesty that he gave him, all people, nations, and languages trembled and feared before him: whom he would he slew, and whom he would he kept alive, and whom he would, he set up, and whom he would he put down .

He ruled arbitrarily, and had power of Life and Death, he did what he would, his will was a Law. And this lifted up his Heart in pride, and hardened it as Pharaohs, for which being incorrigible, he was deposed from his Kingly Throne, as in the next verse.