So Loki was captured and changed back into his own shape, sullen and fierce. But he had no word of sorrow for his evil deeds; nor did he ask for mercy, for he knew that it would be in vain. He kept silent while the Æsir led him all the weary way back to Asgard.
Now the whole world was noisy with the triumph of his capture. As the procession passed along it was joined by all the creatures who had mourned for Balder, – all the creatures who longed to see Loki punished. There were the men of Midgard, the place of human folk, shouting, "Kill him! kill him!" at the top of their lungs; there were armies of little mountain dwarfs in their brown peaked caps, who hobbled along, prodding Loki with their picks; there were beasts growling and showing their teeth as if they longed to tear Loki in pieces; there were birds who tried to peck his eyes, insects who came in clouds to sting him, and serpents that sprang up hissing at his feet to poison him with their deadly bite.
But to all these Thor said, "Do not kill the fellow. We are keeping him for a worse punishment than you can give." So the creatures merely followed and jostled Loki into Asgard, shouting, screaming, howling, growling, barking, roaring, spitting, squeaking, hissing, croaking, and buzzing, according to their different ways of showing hatred and horror.
The Æsir met on Ida Plain to decide what should be done with Loki. There were Idun whom he had cheated, and Sif whose hair he had cut off. There were Freia whose falcon dress he had stolen and Thor whom he had tried to kill. There were Höd whom he had made a murderer; Frigg and Odin whose son he had slain. There was not one of them whom Loki had not injured in some way; and besides, there was the whole world into which he had brought sorrow and darkness; for the sake of all these Loki must be punished. But it was hard to think of any doom heavy enough for him. At last, however, they agreed upon a punishment which they thought suited to so wicked a wretch.
The long procession formed again and escorted Loki down, down into a damp cavern underground. Here sunlight never came, but the cave was full of ugly toads, snakes, and insects that love the dark. These were Loki's evil thoughts, who were to live with him henceforth and torment him always. In this prison chamber side by side they placed three sharp stones, not far apart, to make an uneasy bed. And these were for Loki's three worst deeds, against Thor and Höd and Balder. Upon these rocks they bound Loki with stout thongs of leather. But as soon as the cords were fastened they turned into iron bands, so that no one, though he had the strength of a hundred giants, could loosen them. For these were Loki's evil passions, and the more he strained against them, the more they cut into him and wounded him until he howled with pain.
Over his head Skadi, whose father he had helped to slay, hung a venomous, wriggling serpent, from whose mouth dropped poison into Loki's face, which burned and stung him like fire. And this was the deceit which all his life Loki had spoken to draw folk into trouble and danger. At last it had turned about to torture him, as deceit always will do to him who utters it. Yet from this one torment Loki had some relief; for alone of all the world Sigyn, his wife, was faithful and forgiving. She stood by the head of the painful bed upon which the Red One was stretched, and held a bowl to catch the poison which dropped from the serpent's jaws, so that some of it did not reach Loki's face. But as often as the bowl became full, Sigyn had to go out and empty it; and then the bitter drops fell and burned till Loki made the cavern ring with his cries.
So this was Loki's punishment, and bad enough it was, – but not too bad for such a monster. Under the caverns he lies there still, struggling to be free. And when his great strength shakes the hills so that the whole ground trembles, men call it an earthquake. Sometimes they even see his poisonous breath blowing from the top of a mountain-chimney, and amid it the red flame of wickedness which burns in Loki's heart. Then all cry, "The volcano, the volcano!" and run away as fast as they can. For Loki, poisoned though he is, is still dangerous and full of mischief, and it is not good to venture near him in his torment.
But there for his sins he must bide and suffer, suffer and bide, until the end of all sorrow and suffering and sin shall come, with Ragnarök, the ending of the world.