Titus 2:6-8

In a similar way urge the young men to be sensible and self-controlled and to behave wisely [taking life seriously]. And in all things show yourself to be an example of good works, with purity in doctrine [having the strictest regard for integrity and truth], dignified, sound and beyond reproach in instruction, so that the opponent [of the faith] will be shamed, having nothing bad to say about us.