... That which caused the burning of the worthy Njall his wife and sons, in their house, was the taunt of a certain Skarpedin, who threw a pair of breeches at a certain Flossi and bade him wear them, as he was a woman every ninth day.  This was an insult that could be expunged only with blood or fire.  In the Gullathing laws is one condemning to outlawry any man who charged another with change of sex, or with having given birth to a child.  When Thorvald the Wide-travelled went round Iceland with a German missionary Bishop named Frederick, preaching the Gospel, the smooth face and long petticoats, and perhaps the portly paunch of the prelate, gave rise to bitter jests.  A local poet sang:

"Nine bairns born
The Bishop hath,
And of all and eke
Is Thorvald father."

This was more than Thorvald could endure, and he hewed down the scald with his battle-axe. (Family Names and Their Story, Baring-Gould, 1910).