There is a short story in this connection about a snake who became a devotee upon instruction by Narada, who instructed him not to bite anymore. Since ordinarily a snake's business is to fatally bite other living entities, as a devotee he was forbidden to do so. Unfortunately, people took advantage of this nonviolence on the part of the snake, especially the children, who began to throw stones at him. He did not bite anyone, however, because it was the instruction of his spiritual master.
After a while, when the snake met his spiritual master, Narada, he complained, "I have given up the bad habit of biting innocent living entities, but they are mistreating me by throwing stones at me." Upon hearing this, Narada Muni instructed him, "Don't bite, but do not forget to expand your hood as if you were going to bite. Then they will go away." Similarly, a devotee is always nonviolent; he is qualified with all good characteristics. But, in the common world, when there is mischief made by others, he should not forget to become angry, at least for the time being, in order to drive away the miscreants.