I urge you, brothers, to watch out for those who create dissensions and obstacles, in opposition to the teaching that you learned; avoid them. For such people do not serve our Lord Christ but their own appetites, and by fair and flattering speech they deceive the hearts of the innocent. For while your obedience is known to all, so that I rejoice over you, I want you to be wise as to what is good, and simple as to what is evil; then the God of peace will quickly crush Satan under your feet....