>11. Give up blood sports.

I think he is suggesting not to watch blood sports, that is to say not to spend a lot of time watching a human beat up another human for your enjoyment. Considering that it's Barlow I suppose the time it was written at was one where boxing was more relished as a viewer past-time in the U.S.

Yes, good thing we are past that and on to "game of thrones" or whatever the current nudity + violence trend is.

Try an experiment-- count how many people you saw killed by other people in the last week across all of the media you "consumed" (include the ones where the camera cut away at the last second)

Give up unnecessary conflict, or, give up conflict where the goal is to make the other person suffer or bleed.

To be out for blood is to seek revenge. I read "Give up blood sport" as a caution against doing so.

the way I've understood 'blood sport' was that the particular sport never matters, the important parts are the viciousness and cruelty involved. so for me, martial arts = sports, and cockfighting = blood sport.