Titus 1:9

9 He must hold firm to the trustworthy word as taught, so that he may be able to give instruction in sound doctrine and also to rebuke those who contradict it.

Titus 1:13

13 This testimony is true. Therefore rebuke them sharply, that they may be sound in the faith,

Titus 2:2

2 Older men are to be sober-minded, dignified, self-controlled, sound in faith, in love, and in steadfastness.