having a good conscience; that, wherein ye are spoken against, they may be put to shame who revile your good manner of life in Christ.

keeping a clear conscience, so that those who slander you may be put to shame by your good behavior in Christ.

having a good conscience, that in that in which they speak against you as evil-doers, they may be ashamed who are traducing your good behaviour in Christ;

having a good conscience, that [as to that] in which they speak against you as evildoers, they may be ashamed who calumniate your good conversation in Christ.