This poem from the Elder Edda is a flyting, or poetic duel of insults, between Loki and all the gods and goddesses of Asgard.
The gods gathered in Asgard for a drinking party with the ale prepared by Gymir in his huge kettle. Loki crashed the party and began insulting each person in turn. Odin can't turn him away, since he is a blood brother; violence is forbidden in the hall of the gods, so no one can kick Loki's ass, either.
Odin mentions that Loki was turned into a woman, gave birth to babies, and breast-fed them; Loki accuses Frigg, Odin's wife, of being a bisexual slut. The insults get ruder and ruder. Particularly memorable is this verse:
Enough, Freya! I know you a witch
Who has done many wicked deeds:
You enticed into bed your own brother, remember,
And then, Freya, you broke wind.
Finally, Thor threatens Loki with the hammer Mjolnir. Loki flees and hides, but eventually is caught by the gods and chained to a rock with the entrails of one of this sons.
The quote above is from the translation by P.B. Taylor and W.H. Auden; I have also seen an English translation by Patricia Terry.