Sif is the golden-haired Norse goddess of wheat and prosperity. She is also the wife of the thunder-god Thor, and the mother to their daughter, Þrúðr. She has a son, Ullr, from her previous relationship, which is relatively obscure. Not much is known about Sif, save that she was very vain until her hair was shorn by Loki as a practical joke. Her hair was restored to her by the two dwarf sons of Ivaldi when Loki goaded them into a bet against the dwarfs Brokk and Eitri.
In the Lokasenna
In the poem Lokasenna, Loki engages in a competition of flyting (the exchange of insults) with the Æsir in Ægir's hall. During this, Loki exchanges insults with many of the gods and, when Sif goes to pour for him, she asks him to leave her alone as she is blameless, however Loki claims to have had an affair with her. Such an event is never mentioned in any other prose.
Sif: "Hail to thee, Loki!
- and this cool cup receive,
- full of old mead:
- at least me alone,
- among the blameless Æsir race,
- leave stainless."
- "So alone shouldst thou be,
- hadst thou strict and prudent been
- towards thy mate;
- but one I know,
- and, I think, know him well,
- a favoured rival of Hlórridi1,
- and that is the wily Loki."
In the 2010 Thor film she is referred to as Lady Sif, and has black hair instead of golden.
1Another name for Thor.