Testimony for witness, A.V.; for which cause for wherefore, A.V.; reprove for rebuke, A.V. Sharply ( ἀποτομῶς); elsewhere only in 2 Corinthians 13:10 (see also Romans 11:22). That they may be sound (see Titus 2:2).
The faithful pastor must use severity when it is necessary to the spiritual health of the flock, just as the skilful surgeon uses the knife to save the patient's life.