Titus 1:9; Titus 1:13; Titus 2:1-2

9 Holding fast the faithful word as he hath been taught, that he may be able by sound doctrine both to exhort and to convince the gainsayers .
13 This witness is true. Wherefore rebuke them sharply, that they may be sound in the faith;
1 But speak thou the things which become sound doctrine: 2 That the aged men be sober, grave, temperate, sound in faith, in charity, in patience.