A more thorough explanation:

BYRTHYNSAK

byrthynsak (bər-thən-sak), n.
[Anglo-Saxon byrthen “burden” + sacu “lawsuit”]
Hist. The theft of a calf or ram that is the most a man can carry on his back.

Byrthynsak is a word that comes from Old English. It means stealing a calf or a ram that is so heavy that a person can only carry it on their back. This word was used a long time ago when people had to carry things by themselves and didn't have cars or trucks to help them.

Example 1: John was caught for byrthynsak when he stole a calf from his neighbor's farm. He was only able to carry it on his back because it was so heavy.

Example 2: Mary was accused of byrthynsak when she stole a ram from the market. She was caught because she was struggling to carry it on her back.

These examples show how byrthynsak was used in the past to describe a specific type of theft. The word was used to describe stealing a calf or a ram that was so heavy that a person could only carry it on their back. This type of theft was common in the past when people had to carry things by themselves.