Titus 1:9 - 1:11
9 holding fast the faithful word which is in accordance with the teaching, so that he will be able both to exhort in sound doctrine and to reprove those who contradict. 10 For there are many rebellious men, empty talkers and deceivers, especially those of the circumcision, 11 who must be silenced because they are upsetting whole families, teaching things they should not teach for the sake of dishonest gain.
Titus 1:13
13 This testimony is true. For this reason reprove them severely so that they may be sound in the faith,
Titus 2:1
Instructions for the Older and Younger
But as for you, speak the things which are proper for sound doctrine.
Titus 2:15
15 These things speak and exhort and reprove with all authority. Let no one disregard you.