'Soundness' in the Bible

And his name through faith in his name hath made this man strong, whom ye see and know: yea, the faith which is by him hath given him this perfect soundness in the presence of you all.

not paying attention to Jewish myths and the commandments and rules of men who turn their backs on the truth.

concerning everything showing yourself [to be] an example of good deeds, in your teaching [demonstrating] soundness, dignity,

and soundness of speech that can't be condemned; that he who opposes you may be ashamed, having no evil thing to say about us.