If we do not prepare to life a good life (cf James 3:13) then we will prepare to do evil; because the is no morally neutral place for our thoughts and ambitions.
It used to be said in London, that you could wait a long time for a bus, and then three would come together. Likewise, one evil rarely comes without the company of others.
Worldly wisdom seems to be a cross between common sense and past experience of success, but impregnated by self interest. God's wisdom is very different.
Violence may roam around the world, but it has no part in the kingdom of heaven. Fights are personal struggles between people and will inflict pain and damage.
Is jealousy good or bad? To be jealous over something or someone that does not belong to you is bad: but it is right for a husband and wife to be jealous over each other. They belong together.