Question: Where does the phrase "hate your guts" (for example "I hate your guts") come from?

I've heard the phrase used as a way to convey extreme and deep dislike of another individual. However, it seems strange to have just been born arbitrarily and I suspect there is a source.

Answer: 
I have no background in languages; but thought I'd add my two cents. Use of the word "guts" to describe feelings that are go to our core is clear. Aside from location and disgusting visual appearance, there may be also be an association with the abdominal gripping sensation our bodies feel when our nervous system kicks in.
I have a theory that the phrase comes from one of the two characteristics of Kosher animals which requires an animal to have more than one stomach. If an animal has non-Kosher-style stomachs (i.e. like a pig) it is not-Kosher (and sometimes seen as not pure). 

Perhaps insulting someone's guts was a way of saying they are like a pig, or other impure animal.