Albert Barnes Commentary Titus 2:15

"These things speak and exhort and reprove with all authority. Let no man despise thee." — Titus 2:15 (ASV)

These things speak and exhort. (See Barnes' Notes on 1 Timothy 6:2).

And rebuke with all authority. (See Barnes' Notes on 1 Timothy 5:1, 1 Timothy 5:20; and 2 Timothy 4:2).

The word authority here means command (epitagh). (Compare 1 Corinthians 7:6, 25; 2 Corinthians 8:8; 1 Timothy 1:1; Titus 1:3).

The sense here is, he was to do it decidedly, without ambiguity, without compromise, and without keeping anything back. He was to state these things not as being advice or counsel, but as the requirement of God.

Let no man despise you. That is, conduct yourself, as you may easily do, so as to command universal respect as a minister of God. (See Barnes' Notes on 1 Timothy 4:12).

Titus - Chapter 3