3:19-27 Let Nebuchadnezzar heat his furnace as hot as he can, a few minutes will finish the torment of those cast into it; but hell-fire tortures, and yet does not kill. Those who worshipped the beast and his image, have no rest, no pause, no moment free from pain, Re 14:10,11. Now was fulfilled in the letter that great promise, Isa 43:2, When thou walkest through the fire, thou shalt not be burned. Leaving it to that God who preserved them in the fire, to bring them out, they walked up and down in the midst, supported and encouraged by the presence of the Son of God. Those who suffer for Christ, have his presence in their sufferings, even in the fiery furnace, and in the valley of the shadow of death. Nebuchadnezzar owns them for servants of the most high God; a God able to deliver them out of his hand. It is our God only is the consuming fire, Heb 12:29. Could we but see into the eternal world, we should behold the persecuted believer safe from the malice of his foes, while they are exposed to the wrath of God, and tormented in unquenchable fires.
19. visage … changed—He had shown forbearance (Da 3:14, 15) as a favor to them, but now that they despise even his forbearance, anger "fills" him, and is betrayed in his whole countenance.
seven times more than it was wont—literally, "than it was (ever) seen to be heated." Seven is the perfect number; that is, it was made as hot as possible. Passion overdoes and defeats its own end, for the hotter the fire, the sooner were they likely to be put out of pain.