On most of Thor’s expeditions, Loki acted the part of a friend, outwardly at least. Between Heimdal and Loki, on the contrary, there was deadly enmity without ceasing. This enmity showed itself, for example, on the occasion when Loki had stolen the Necklace of the Brisings from Freyja. Loki hid the ornament in the sea at Singastein, and kept guard over it himself in the shape of a seal. Heimdal likewise assumed the likeness of a seal, and so compelled Loki to restore what he had stolen. This is the probable interpretation of the casual references in Snorri’s Edda, in which case we have here to do with the old and authentic form of the myth. A variant of the myth, quite different and far less primitive, is to be found in the legendary Sorla þáttr, dating from the thirteenth century. According to this account, Freyja had received the necklace from four Dwarfs; Odin, however, coveting it, asked Loki to steal it for him. It would prove to be a difficult task, Loki said, for Freyja’s
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