Titus 1:9

1:9 He must hold firmly to the faithful message as it has been taught, so that he will be able to give exhortation in such healthy teaching and correct those who speak against it.

Titus 2:7-8

2:7 showing yourself to be an example of good works in every way. In your teaching show integrity, dignity, 2:8 and a sound message that cannot be criticized, so that any opponent will be at a loss, because he has nothing evil to say about us.