Because of a Horse, A Viking Could Kill You
Indeed, the majority of the Vikings were farmers but it didn't mean the Vikings would never hurt anyone. Many of Viking warriors were originally farmers who became famous for their ferocity. In Viking saga, a Viking killed their neighbor because that neighbor touched his horse.
The story happened in Iceland early 900s. There was a chieftain whose name was Hrafnkel and he was a pagan in his blood. Hrafnkel was believed to worship Freyr and was a messenger of this god. His horse was Freyfaxi.
The master and his Freyfaxi horse
Hrafnkel was nice and generous with his men but he would spare no life for his enemies. There was no definition of an enemy for Hrafnkel. Anyone who made him angry would have to pay the ultimate price. His final limit was Freyfaxi. The horse was of the most importance to Freyfaxi.
Einar was a shepherd working on the farm of Hrafnkel. His responsibility was to make sure that all livestock came into their house before the night fell on.
One day, Einar couldn't call all livestock back home and he came up with "borrowing" the horse of his master. He approached Freyfaxi and rode him around the field. And with the help of the mighty horse, Einar finally completed his mission of that day. He let go of Freyfaxi and the horse came back to his master.
To complete his mission, the shepherd had to borrow Freyfaxi the Horse
Hrafnkel knew everything about Freyfaxi. Any change on his horse would make him notice. He saw his favorite horse sweating and full of dirt. The next morning, he came to the farm and found Einar.
The two argued about the horse and the vow of Hrafnkel. Because the master had made a vow that he would never let anyone touch his horse and those who dared to violate it would have to pay the ultimate price. After changes of words, Hrafnkel took out his sword and beheaded Einar for his violation.
And that's why we say don't piss a Viking off because he will let his sword speak to you.