See here, 1. How we may discern a fool and discover him, a wicked man, for he is a foolish man. If we perceive not in him the lips of knowledge, if we find there is no relish or savour of piety in his discourse, that his communication is all corrupt and corrupting, and nothing in it good and to the use of edifying, we may conclude the treasure is bad. 2. How we must decline such a one and depart from him: Go from his presence, for thou perceivest there is no good to be gotten by his company, but danger of getting hurt by it. Sometimes the only way we have of reproving wicked discourse and witnessing against it is by leaving the company and going out of the hearing of it.