...and appoint elders in every city as I directed you, namely, if any man is above reproach, the husband of one wife, having children who believe, not accused of dissipation or rebellion. For the overseer must be above reproach as God's steward... Titus 1:5-6

Deacons in like manner [must be] grave, not double-tongued, not given to much wine, not greedy of filthy lucre; holding the mystery of the faith in a pure conscience. And let these also first be proved; then let them serve as deacons, if they be blameless. 1 Timothy 3:8-10

...preach the word; be ready in season and out of season; reprove, rebuke, exhort, with great patience and instruction. 2 Timothy 4