KJV - 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.
ASV - holding to the faithful word which is according to the teaching, that he may be able to exhort in the sound doctrine, and to convict the gainsayers.
BBE - Keeping to the true word of the teaching, so that he may be able to give comfort by right teaching and overcome the arguments of the doubters.
WEB - holding to the faithful word which is according to the teaching, that he may be able to exhort in the sound doctrine, and to convict those who contradict him.
YLT - holding -- according to the teaching -- to the stedfast word, that he may be able also to exhort in the sound teaching, and the gainsayers to convict;