One of the clear teachings of the Sermon on the Mount is Jesus' insistence that we pay attention to what he says and stop listening to the other voices that crowd in on our thoughts. Everything in me resists wanting to hear that. I don't want such language to penetrate very far. I want to protect myself, to not take seriously all the risks that go with that. The world in fact will threaten us.
Persecution can be that overt, or it can be more subtle.
People will cut us off, deny us opportunities for advancement, misunderstand us, shut us out of relationships, and isolate us. The world will threaten us, and the noise of the world's threat can drown out the words of Jesus so that we don't hear them as well. The arguments of those who would twist the Law also sound in our ears. Applause can sometimes drown out the words of Jesus. That is another warning of his.