Said Thor: Little as you call me, let anyone who likes come hither and wrestle with me, for now I am wroth. Answered Utgard-Loke, looking about him on the benches: I do not see anyone here who would not think it a trifle to wrestle with you. And again he said: Let me see first! Call hither that old woman, Elle, my foster-mother, and let Thor wrestle with her if he wants to. She has thrown to the ground men who have seemed to me no less strong than Thor. Then there came into the hall an old woman. Utgard-Loke bade her take a wrestle with Asa-Thor. The tale is not long. The result of the grapple was, that the more Thor tightened his grasp, the firmer she stood. Then the woman began to bestir herself, and Thor lost his footing. They had some very hard tussles, and before long Thor was brought down on one knee. Then Utgard-Loke stepped forward, bade them cease the wrestling, and added that Thor did not need to challenge anybody else to wrestle with him in his hall, besides it was now getting late.

- Prose Edda (The Fooling of Gylfe, XIV)