A Christian that camouflages themselves in the ways of the world is no better than a dog that returns back to their own vomit (Pro. 26:11); if they answer a fool according to their folly, the one who claims to know better will become like that fool, but if that Christian answers according to their worldly ways, that fool will then become wise in their own eyes (ver. 4-5) - denying the Word of power in true and proper evangelism!